Tora was the first unit after the release of 7* that was centered around status ailments. Following her release, we got Fadahl, then Vernil, then Kafka, whom is the best non-Global exclusive status inflictor.
Kafka is the only unit in the game can apply all status ailments to enemies, with the exception of debuff-type ailments (Attack Down, Defense Down, etc). Kafka's SBB has a 10% chance to apply Injury/Weakness/Sickness and 7% chance to apply Paralyze/Curse/Poison. However, this is a buff that is added to her attack as well as the rest of the party for 3 turns. So for the next three turns all of your units have a chance to apply status ailments when they do normal attacks and use their BB/SBB/UBB.
Semira, however, is hands down the best status inflictor in the game. Her SBB has a whooping 80% chance of applying Curse/Paralyze/Poison/Weak. But it's her SBB that has that chance, it isn't a attack buff added to everyone's attack like Kafka's.
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