Vanille – Ravager Crystarium

Character Vanille
Role Ravager
Vanille is a good Ravager with a number of holes in her Ability list. Like Hope, she lacks any -strike Abilities, making her unable to damage enemies that are immune to Magic. She can still advance their chain bonus (and doesn't need to worry about strength!), but this can be a big problem against certain foes. She also lacks Aeroga, Thundaga, and Waterga, and doesn't get the Vigor Ability. None of this is crippling, but it does set Vanille firmly behind Hope as far as Ravagers go.
Compare Vanille – Ravager Crystarium to other Crystariums

Related

Vanille

Eidolon Hecatoncheir (Chapter 11)
Base HP 350
Maximum HP 21,050
Base Strength 23
Maximum Strength 1,400
Base Magic 35
Maximum Magic 1,700
Starting Weapon Binding Rod
Primary Roles Ravager, Saboteur, Medic
Accessory Crystal Saboteur 5
Accessory Crystal Medic 8
Accessory Crystal Ravager 10
ATB Level Crystal Medic 8
Chapter 1

Fang – Ravager Crystarium

Character Fang
Role Ravager
For a secondary Role, Fang is a damn effective Ravager. (This seems even stranger since she's the only Character who doesn't have Ravager as a primary Role.) She has access to every spell through tier 2, and while she only has two -ga spells, one of them is Aeroga! Perhaps her biggest disadvantage as a Ravager is that her strength is so high that she's more effective in other Roles. However, she does gain all four -strike Abilities, so even this isn't really a problem.

Hope – Ravager Crystarium

Character Hope
Role Ravager
Hope is the best Ravager in the game, provided your target is not more vulnerable to Physical than Magic attacks. The only Abilities Hope lacks are the -strike Abilities, which is usually fine but will occasionally make him virtually useless. Hope also has the Last Resort special Ability, which will very rapidly build the chain bonus of a staggered target.

Lightning – Ravager Crystarium

Character Lightning
Role Ravager
Ravager is perhaps Lightning's best overall Role. She gets a complete set of auto Abilities and every spell in the first two tiers. What she lacks is -ga spells, getting only Thundaga. While you can certainly live without them, the lack of Aeroga in particular is a bit painful. On the upside, her unique Army of One Ability is fantastic for building chain bonuses against staggered opponents, and combos very well with her Attack: ATB Charge Weapons.

Sazh – Ravager Crystarium

Character Sazh
Role Ravager
Sazh has no access to Blizzard or Water Abilities, but he does have all three tiers of Fire, Thunder, and Aero spells, along with the relevant -strike Abilities. He does oddly lack the Vigor auto Ability. His Cold Blood special attack will build the chain gauge of staggered opponents quite rapidly.

Snow – Ravager Crystarium

Character Snow
Role Ravager
Snow is the complementary Ravager to Sazh, gaining access to all tiers of Blizzard and Water spells but lacking Fire and Thunder (including the related -strike Abilities). Snow does get Vigor, but lacks Aeroga, which is a powerful crowd control spell. By having access to only two Elements (and the first two tiers of Aero), you have to pay attention to an enemy's weakness before using Snow as a Ravager.

Vanille – Commando Crystarium

Character Vanille
Role Commando
Vanille is the most limited Commando in the game (and has the silliest Weapon), lacking both Launch and Blitz. She does get Blindside and Faultsiphon, auto Abilities that are easy to take advantage of. However, her Role should generally be limited to that of a secondary Commando. She's more useful for the Augmented Attack effect than actual Commando Abilities.

Vanille – Medic Crystarium

Character Vanille
Role Medic
Vanille and Hope are the only Characters with access to every Medic Ability, and while Hope's magic stat is naturally higher, Vanille is plenty effective as a Medic as well. She and Hope are the only Characters who can use the amazing Curaja Ability, a vital healing spell in the endgame.

Vanille – Saboteur Crystarium

Character Vanille
Role Saboteur
Vanille is a very effective Saboteur with a variety of Abilities, though she is more concentrated on defense-lowering debuffs. She cannot inflict Slow, Curse, or Daze, and also lacks Fogga and Painga, but has single- and multi-target versions of every other Saboteur Ability. Beyond that, she has Death, a unique Ability that either just kills a target or deals a large amount of damage to them. Since very few non-boss enemies are actually immune to Death, you can get cheap, fast kills against a number of difficult foes (up to and including Adamantoises) with it.

Vanille – Sentinel Crystarium

Character Vanille
Role Sentinel
Vanille as a Sentinel? Surely not! And truth be told, she's not very good at it. She has Mediguard at least, but not much else, including Challenge. She does have more HP than Lightning or Hope, but both of them are evasion Sentinels anyway. Basically, you don't want Vanille to be your main Sentinel. She's fine in the Tortoise (SEN/SEN/SEN) paradigm, but not much else.

Vanille – Synergist Crystarium

Character Vanille
Role Synergist
Along with Fang, Vanille is one of two Characters that has access to Bravera, Faithra, Protectra, and Shellra, high-powered Abilities that have a short duration to balance their extra effectiveness. Unlike Fang, Vanille has a decent number of standard Synergist Abilities as well, including Veil, Vigilance, and the Bar-spells. She is the only Character in the game that doesn't get Haste, however, so she's not very effective as your only Synergist.

Ravager

Bonus Type Improved Chaining

Ravager

Abbreviation RAV
Role Bonus Improved Chaining
Base Bonus (Self) Chain Bonus: +1.0%
Role Level I Bonus (Self) Chain Bonus: +2.0%
Role Level II Bonus (Self) Chain Bonus: +3.0%
Base Bonus (Allies) Chain Bonus: +0.1%
Role Level II Bonus (Allies) Chain Bonus: +0.2%
Role Accessory Blaster's Sapphire (Grants Chain Bonus: +0.5% to self)