Welcome to the world of monster infusion! In FFXIII-2, the game's resident “goddess,” Etro, has given a special gift to Serah (presumably Lightning, too, but Serah's the one that you play as). When she fights some monsters (no cie'th, no bosses except Twilight Odin and DLC) and kills them, there's a chance (varying from 3% to 100% by monster) that their essences will coalesce into crystals. Serah harvests these crystals and mentally activates them, so they magically generate their respective bodies with their respective capabilities to fight at Serah's side. Once summoned, they operate independently, so they don't become useless every time that she's KOd.
Note that she can only keep one monster active at a time. If she could summon any more at once, a speed run would be a matter of who has the most millisecond-accurate stopwatch, and that'd be for the whole game, not just one battle!
Also, remember that the term, “monsters,” is being bandied about liberally. It includes machines, some manifestations of other beings (Lightning, Amodar, Nabaat), some summons/bosses (Twilight Odin, Typhon, Ultros), a weapon-collecting, superhuman character with comic relief to spare that is based on a mythological person (Gilgamesh), and. . . I. . . I don't know how to classify Pupus. ._.
Before anyone asks, there is no way for a monster to change its role. The two humans simply switch their tactics and role bonuses at command, but switching roles with your third unit means switching monsters. A Silver Chocobo will always be a SEN; if you want a MED monster in play, you switch to a Green Chocobo.
HP is kinda' “shared” between monsters. Don't get me wrong; you never get their combined total. They are proportionally transferred. In other words, if one monster has 10,000 HP and loses 4,000 (40%), then you switch to a monster with 5,000 HP, that second monster will be 2,000 (40%) down. If that monster then heals up to full and you switch back, the other monster will come in full. If you switch to a fragile monster and it gets KOd, switching monsters will not save you; they'll all come in Kod.
Monster Materials
You use items by the name of “monster materials” (mats) to increase the levels of your monsters, which increases their stats and parameter (in this game, just Strength, Magic, and HP). Monsters naturally have some abilities from Lv1 (default) and naturally learn more at higher levels.
There are different “grades” of mats and two categories. The two categories are for the biological and mechanical monsters. Don't worry; when you're in a given monster's crystarium, only items of the right category will appear. The following mats correspond to the numbered grades (bio/mech):
- Droplets/Bolts
- Slivers/Chips
- Orbs/Engines
- Essences/Boosters
- Crystals/Generators
At low levels, you'll only spend one or a few mats to advance a level. Every few levels, though, the cost will go up a bit, so you'll end up spending 6 or 7 materials for each level as you get up there. With each expansion, though, the cost gets set back to one, just at the next grade up. If the grade can't advance (maximum of 5), the cost doesn't reset.
The main question is about the four monster mat “types.” There are vitality, power, mana, and potent items. Each monster can be optimized with a different set of each (some all power, some all mana, some all potent, some potent here and power there, et cetera), but here're the general statements about them:
VIT- Don't use these. Most non-Sentinel (SEN) monsters have more HP than they need, and all half-decent SENs have plenty, especially when infused with defensive, passive abilities. Do note, however, that DLC is being released with more difficulty each time. There may come a day in which VIT mats come into style; it's just hard to imagine at this point.
PWR- You'll see use for a lot of these. STR-based units, mainly Commandos (which includes almost all top-tier COMs, the only exception being marginally better than another for farming Raspatl), should get lots of these and maybe some PTN mats to balance their HP up to snuff.
MAN- Likewise, these are the best for MAG-based units, inclusive of almost all top-tier Ravagers (RAVs), all present Medics (MEDs), almost all Saboteurs (inclusive of all top-tier, the only SABs that will see practical usage), and all Synergists (SYNs). Do note that RAVs tend to be a bit fragile, though, so you may want to see their optimization paths for potent/mana builds if you are oddly using a particularly fragile RAV against a particularly strong foe. This is not typically advised, though, as good RAVs are just tough enough to get by, and their magic is important.
PTN- These will see the absolute most usage. They give a smaller boost to all three selections, and it's enough that they're better as long as you're raising two things at once. Their main downfall is that HP is only so valuable, and most monsters only have use for STR or MAG, so specialization often becomes the best choice, with potent thrown in some places to balance HP out enough. Going with all potent mats is the easy way out, especially since you can eventually buy the grade 5 variants, unlike the others. It's also the best for Silver Chocobo and some other SENs because you want all three selections.
For complete info on what the best item usage plans are for each monster, view either of these spreadsheets:
https://docs.google.com/spreadsheet/ccc?key=0Apa6evZUmvfHdGJLSUd5RWpJUzdsSmZ4SEpKckR4R1E#gid=12
http://www.mediafire.com/?3qnxkdjrmi9ka2h
Thread with known errors: http://www.gamefaqs.com/boards/619315-final-fantasy-xiii-2/62632365
Expansion Bonuses
Crystarium Expansions have an actual purpose, you know? The occur at intervals that differ in respect to the maximum level of the monster, but higher level caps = more expansions is a true rule. Lv99 monsters receive four expansions. The purpose of all of this is, aside from the grade/cost variances, you get to pick a bonus at each expansion, just like the chars. There are just two different bonuses for monsters: ATB Gauge + 1 (maximum of six segments) and Role Bonus Boost (maximum of Role Bonus Boost II). Since most monsters start with three ATB segments, Lv99 monsters have to chose between three ATB and one Role Bonus Boost or two of each. TO is the exception because he starts with four ATB segments. Monsters that get just two expansions should spring for 4 ATB and Role Bonus Boost, with an arguable exception for RAVs, while those with a single expansion should just get 4 ATB. You can read around for the discussions of why (A lot of it has to do with ATB Refresh and AI.), but here are the most up-to-date conclusions for what choices to make (though you should be aware that none of these make a dramatic difference, so don't feel compelled unless you want the best of the best):
Paradigm Pack: This is the organization of three monsters that you select to use, so called because they are individually assigned to your party's “paradigms” (strategic organizations of roles to be used in unison) to form three-unit paradigms. Henceforth, this is simply called your “pack.”
Target: Here's the monster that you are working on, presumably to keep and fight with. If you are presently infusing into it, it can't be in your pack, so take it out to work on it, then put it back in to use it.
Existing: An existing ability is simply one that your target already knows. If you're infusing onto a monster that will later be infused onto the target, its existing abilities must be considered, too.
RL: A red-locked passive is naturally learned. It can't ever be lost, no matter what (often a hindrance), and it can't be infused onto another monster (often a disappointment for unique abilities/Pack Mentality). You can't unlock it, you can't put a yellow lock on it, but you can upgrade it. If a monster has, say, an RLed ATB Advantage (like Black Chocobo), you can infuse First Strike onto it to upgrade it. This doesn't get rid of the RL, though. Don't worry; there are a few good uses for RLs.
YL: A yellow-locked passive has its rank artificially increased by 9. We'll get into the significance of that in a bit, but the basic idea is that it'll get locked in above any unlocked abilities. These are just as useful as RLs for filtering (though RLs have the advantage of naturally existing in sufficient numbers on the right monsters) and are often used to keep wanted passives of low ranks when you already have some highly-ranked, unwanted passives. They are integral to infusion strategies that you need to get the right abilities for good builds, so learn their mechanics below!
Junk: Junk is a monster whose name doesn't matter. It should have no unwanted passives that are moderately-highly ranked, and it shouldn't have lowly-ranked, unwanted passives if you infuse an even number of copies, 'cause you'll then have a yellow-locked turd in your way. This is usually for external YLing and learning “hidden role abilities.” Do not confuse these with filters.
Noise: Passives that are lowly-ranked and easily obtained are either used with YL mechanics to lock in highly-ranked, wanted passives, or are used as flush materials.
Flush material: A passive that is lowly-ranked (R4-, sometimes R5- or even R6-), not wanted on your target, not an inferior version of an existing passive, and easily obtained (e.g. Resist Wind +10% from a Lv7 Chocobo or Resist Fire +10% from a Lv1 Clione) is YLed (often externally), infused onto the target to push off or keep off unwanted, usually highly-ranked passives, then unlocked so that it can easily be replaced by lowly-ranked, wanted passives.
Filter: A monster with locked abilities (often a Hedge Frog or Mud Frog, used for their easily-obtained and numerous RLs) becomes an intermediate target for infusions in order to push off some unwanted, highly-ranked passives before they can every hit your target. They are most often used for scrapping Auto-Veil and/or Magic +35%, especially for a target that naturally learns Pack Mentality without an RL.
This is the simplest part. You simply select the target, go to “Infusion” on the menu, and select the monsters that you wish to infuse. Stats and HP are NOT transferred or counted for anything in any way. If you're raising a monster just to infuse it into another one, the materials that you use on it do not matter.
You select which role ability(ies) to pass on. The monster that is being sacrificed can pass as many as (Crystarium Expansions that it has had + 1) role abilities.
You do not select the passives. They are all shot over, which isn't to say that they all make it onto the list, but they are all sent at once.
If the infused monster and the target are of opposite roles (COM <> RAV, SAB <> SYN, MED <> SEN), the levels of the infused monster are secretly recorded. If this secret number totals to 99 or more, the target gets the hidden role ability.
Ability Types
Note: There has been some dispute over the definitions of Auto-Abilities and Command Abilities. I can't confirm anything right now, so I'm going to write them up together as Auto-Abilities, then change it when/if I receive confirmation otherwise.
Auto-Abilities are self-abilities. This includes Chasers/Feeders, Armor Breaker/Mind Piercer, Stagger: Actions, other role-specific action/support abilities, and monster-exclusive action/support abilities like Heat Blitz and Felgust. Only “role abilities” are transferable, and not even all of them.
Chasers are exclusive to COM monsters. They exist as 'Ailment Chaser,' where “Ailment” is a certain status ailment. An example is “Slow Chaser,” which activates whenever the enemy has Slow. This one is among the least useful because you have so few ways to inflict Slow on enemies. The effect is to increase the monster's STR by 30% when attacking an enemy with the appropriate ailment. Of course, the boost is not kept; it is only applied to attacks that fit this description. Multiple Chasers can't stack for a bigger STR boost. Though 30% doesn't sound like a whole lot, these end up being the determining factor for which COMs are the best for some battles.
Stagger: Actions are different. They're COM-exclusive. The possibilities are Stagger: Wound and Stagger: Drain. Neither is really good. Stagger: Wound turns 10% of your damage into “wound” damage (can't be healed except by a wound potion, which enemies don't have) as long as the foe is staggered. That's not such a bad thing, but it pales in comparison to the effects of other special attack skills, which Stagger: Actions overrule. You'd expect Stagger: Drain to be better, but it doesn't cause your attacks to gain a draining property; it causes you to cast the Drain spell. That wouldn't be a problem if not for the fact that this only exists on monsters that are either A) never worth using, B) friggin' PHYSICAL units, or C) Miniflan, an all right COM that is easily superseded by many others. The worst part about Stagger: Actions is that they overrule Chasers and Armor Breaker/Mind Piercer, so you could be getting 30% extra STR/MAG, but you're getting a power reduction or minimal benefit when the foe is most vulnerable.
Role abilities are exclusive to their particular role, but are transferable. There is a full list in the FAQ, and their effects are listed on the FF wiki. There are actions, like Ruinga and Blitz, and there are supports, like Fearsiphon and Blindside. Role abilities can be transferred during infusion. In the monster that is being sacrificed knows one that the target monster doesn't, you can pick one to be sent over. You can pick an additional one for each Crystarium Expansion that the sacrificed monster has gone through.
Monster-exclusive abilities are like role abilities, but they are non-transferable and only learned by a select handful of monsters. They are often fairly useful. The COM and RAV abilities are mainly learned by mid-tier monsters, though.
Passive Ranks
Passives have pre-determined ranks. These ranks are not necessarily representative of how good/useful they are; they're just how well the passive sticks it out above other passives. Don't worry; the explanation of that second part is what I'm getting to.
These pre-determined ranks are simply expressed in numbers, 1-9. You do not see these numbers, so refer to the Monster FAQ for the full list.
A red-locked passive has an infinite rank and doesn't transfer. If the infused monster has one, it is deleted. If the target has one, it stays. If the infused one has an upgraded version of the target's RLed passive, the passive is upgraded, but keeps the RL (e.g. Black Chocobo has RLed ATB Advantage and you infuse a Lv58 Clematis, which has First Strike, so Black Chocobo has an RLed First Strike).
Passives of higher rank take precedence over those of lower rank. If you have eleven passives, the one of the lowest rank is bumped off.
If they're of the same rank, passives that come later take a position over those that come sooner. Lancer learns Improved Guard (R5), then Improved Ward (R5), so Improved Ward comes out above. If you infuse Lancer onto a monster that only has room for one, Improved Ward slides in, and Improved Guard is lost. (Note: Lancer also learns Feral Speed II (R6) early on. If none of these are on the target already and the target has room for just two abilities at the bottom, FSII and IW come in.)
Just getting on is not a guarantee of staying; if your monster has Ally KO: Power Surge (R5) on a full list and you wish to teach it Improved Ward, infuse a Lancer and watch as Ally KO: Power Surge is tossed away and Improved Ward takes its place (assuming that there is room for FSII or it is already on the list, 'cause you can't naturally obtain Improved Ward without FSII unless you go a roundabout way with filtering).
A YLed ability has its rank increased by 9 as long as the lock is present. This puts it above any unlocked abilities and any locked abilities of lower rank, though still below locked abilities of higher ranks and always below RLs. Generally speaking, the way to get a wanted, lowly-ranked ability over an unwanted, highly-ranked ability is to lock the lower one before it gets pushed off or before you infuse it. You then push off the unwanted, highly-ranked passive with a wanted, highly-ranked passive(s).
That may look like a lot of information, but it'll come as second nature before you know it. The best way to get a grip on it is to test it out. If you can't do that, watch a vid.
YL Mechanics
This stuff is painfully simple, and it's essential to the process. You can find the rules to locking mechanics in the FAQ, or you can read them here in a different form with some relevant notes.
Remember that the basic premise is that the abilities in question must be of the same family in order for them to overwrite/get locked. Resist Physical and Resist Magic passives are totally independent of each other, but Resist Physical +36% will overwrite Resist Physical +16%. Improved Guard and Improved Ward are totally different, but Improved Guard II will overwrite Improved Guard. The only abilities that are in the same family and aren't totally obvious are ATB Advantage and First Strike.
If you infuse a lowly-ranked passive (whether or not it has a YL) onto a target that already has an existing, better version of it (+16% onto the +36%), it is ignored and deleted. However, if the better version was locked, this will unlock it, so that's bad news.
If you infuse a passive (locked or not) onto an equal copy of it (Improved Ward onto Improved Ward, Feral Speed II onto Feral Speed II, Critical: Bravery onto Critical: Bravery), you get the original one locked. Note that this does NOT refresh how “new” the ability is. If you have Improved Ward over Improved Guard and you lock one, then the other, the YLed Improved Ward will remain over Improved Guard no matter what order you did the locking in.
However, if you have a passive already locked and you infuse an equal copy, you will unlock it, even if both are locked! Think of infusing equally-ranked copies as a sort of “YL toggle.”
Here's the fundamental one: If you infuse a passive of a higher rank (locked or not) onto a lower version of it (locked or not), such as Resist Physical +36% onto the +16% version or First Strike onto ATB Advantage, you get the higher passive with a YL, which is exactly what you want. Hence, you will be seeing a lot of infusions in which you use a low-leveled monster to get an R5 ability, then use a different monster at a higher level to lock the R6 variant, and you will see plenty of cases in which R1 crap is used to lock a much better R7 or R8 variant.
Learning an ability naturally (by leveling up in the Crystarium) can throw a wrench in things. If the naturally learned ability is equal to or higher than the existing one, the existing one is deleted, then the natural one comes in, so you get a refresh on “newness,” but no lock, whether or not you already had a lock. If the natural version is lower, nothing happens.
Note: If you infuse the most highly-ranked version first without locking it and later want it locked (e.g. you infuse Resist Physical +36% and naturally learn Kill: Libra, so you want to lock Resist Phy to keep it as you push Kill: Libra out), you're going to pay dearly. You can't lock it with a lower version, so you have to use an equal version, which means going through all the trouble of getting another Lv48 Green Chocobo to get a second Resist Phy +36%. Since unlocking is so cheap and easy, I recommend locking everything as it comes onto your target, then unlocking them as you change your mind about them.
Techniques
RL Negation: RLed abilities are non-transferable, right? If you infuse Lv60 Tezcatlipoca onto Lv1 Bamapama, Bamapama's RLed Resist Physical +26% is upgraded to +36%, but it's still RLed. Infuse that onto Mimi, and the same thing happens with Resist Magic, while Resist Physical +36% is lost, 'cause it was non-transferable. Now, you have a source of Auto-Tetradefense that doesn't come with the Resists, which is good news to Sazh builders! Okay, you caught a Fencer. You leveled it to 19, but you're done building your RAVs; you don't need Quick Stagger. You don't want to just release it, though; you worked hard for that Siphon Boost II! Oh, how convenient: Narasimha, Orion, and Lv12 Svarog all have RLed Quick Staggers. Infuse your Fencer onto one of them, and Quick Stagger is effectively gone, while you're left with Siphon Boost II to infuse wherever you want. Mistakenly overleveled your Tonberry by two levels? No problem! LV4 Koboldroid Yin has an RLed STR +10% to save the day. Got a Critical: Power Surge that you don't want to carry? That's another shining point for Chocobo. You want your Reaver's Crit: BRV, but not Attack: ATB Charge, so you infuse it onto a Goblin or Dragoon. You want Pulse Gladiator's Improved Counter II, but you can't get it without Critical: Tetradefense getting in your way (which is especially bad because it's R8, so you'd have to lock pretty much everything), so you smash Pulse Glad onto Grand Behemoth, Mud Frog, or Tezcatlipoca, and Crit: Tetra is gone. Noticing a pattern, yet? Run a CTRL + F search for "[L]" in the Monster FAQ, and you'll get a more comprehensive list than I care to put into one paragraph.
External YLing: Use this when your target's list is full of ten passives that either have locks or are more highly-ranked than the passive that you want to add. For example, if your target has one RLed passive, 8 others that you want, and Auto-Veil (R7), but you want to add Item Scavenger II (R4), you have to use this either the standard way or for flushing. You infuse the wanted passive or a lower version of it (e.g. Resist Physical +5% for Resist Physical +36%) onto either a junk monster or, if there is one, another monster that has an ability that you wish to infuse. Then, infuse a second copy of the wanted passive (or the first copy, if you had an inferior version to use) onto the extra monster so that it is YLed. When it is infused onto the target, it is already locked (hence the term; it was locked externally, or outside the list of the target), so it can push its way in.
Filtering: You are infusing a monster that carries an ability that you want (most commonly STR +35% on Tonberry) and a highly-ranked ability that you don't want (MAG +35% on Tonberry). Classically, you just lock all the abilities of lower rank than the unwanted ability, infuse that, then infuse the abilities of the same rank that you want to keep (This occurs naturally with STR +35%; because STR +35% is learned by Tonberry after MAG +35%, it already has the "out with the old, in with the new" rule working for it). Simple. What happens if either A) you already infused some abilities of lower ranks and don't want to spend the time and money to replicate them the hard way or B) are working with Chichu without the Snow+Valfodr DLC and thereby can't lock Pack Mentality? B was actually the only real usage for filtering. With the new DLC to get replacement Nanochus and Chichus so that you can lock Pack Mentality, this technique is obsolete, but it still pays to know it if you don't have the DLC or don't want to waste your time on the uncommon Nanochu drop. What you do is take a filter monster (defined at the top; let's use Lv19 Mud Frog as an example) and infuse the good and bad ability (Tonberry, let's say) onto the filter. Because the filter already has several RLs, you're working with a very small pool of passives, which is good, 'cause the aim is to push the bad one out. You infuse wanted abilities of greater or equal rank onto the filter to push off the bad ability. You should check your stuff before you start; if you're not going to have enough (e.g. you have Resist Phy/Mag +36% and Role Resonance, but you already put HP +30% on Chichu and don't want to raise another Forked Cat), you mix in some external YLing if another ability that you want (e.g. Infuse two Gancanaghs with the Tonberry onto Mud Frog. You now have a YLed FSII working for you, and FSII is something that you want, so that's good. Flush filtering is basically this, but with flush materials that you unlock before the filter is infused. You'll get it after you read about flushing.). Anyway, once you're done and the filter only has good abilities, you infuse the filter onto the target, and you're done.
Flushing: This can be an efficient alternative to external YLing in some cases, though it is mostly unnecessary for that unless you've made some significant mistakes. More practically, it can be used to keep unwanted passives that are more obstructive off your target, and it is the only way to get Pack Mentality onto many lists that it would normally not stick to without externally YLing Pack Mentality. In a way, it often incorporates external YLing, but with unwanted abilities. The flush technique can be found here:
http://www.gamefaqs.com/boards/619315-final-fantasy-xiii-2/62172940
To put it as simply as possible, you use a YLed ability like Resist (something) +10%, Resist (some element) +33%, Resist (something) +44%, Item Scavenger II, or some other lowly-ranked passive that you can easily obtain and YL. You infuse it onto the target monster. This pushes out whatever's at the bottom of the list, of course, which is an ability that's highly-ranked and unwanted. Then, you infuse one more copy of that "flush material" ability to unlock it, and you have now used an R4- ability to push out some R7 ability or something. Replace that cheap piece of junk with whatever ability you want, and you're done. Read below for an example.
Flush filtering: Combine two techniques. YLed passives are used with RLed passives when the RLs aren't numerous enough, which is usually when you've made a pretty significant mistake or need a revision long after you've already set something up. Note: Because flushing is obsolete, so is flush filtering.
That's really all that there is to it! There's been a ton of discussion over the various advantages and disadvantages of monster choices, what expansion bonuses to pick, and the mechanics and usefulness of certain abilities. I will direct you to here:
http://www.gamefaqs.com/boards/619315-final-fantasy-xiii-2/62127253
From about halfway through this thread on, there is a ton of useful info and links to other threads with useful info. Don't get me wrong; the first 1.5 threads were good, but they contain a lot of stuff that has been dated by recent discoveries and revelations. As of the last edit to this message, the most recent thread number is 7. Please read everything from mid-2 on. It's a lot of reading, but it's really interesting if you're into it.
