User blog comment:Albert Arlington/Recomend units/@comment-30054866-20180514070234

Hi there! (^^)/

You're going to need to be a fair bit clearer than that. "Gain BB" and "Resist", for example, are pretty large umbrella topics, y'know? (owo)

For BC management (aka "Gain BB"), Daltisk is currently the best unit to have. She pretty much packs every BC-filling buff in the game - burst BC fill, BC over Time, BC drop during Spark and when attacked, BC and HC droprate boosts, and so on. She's admittedly fairly hard to get, though - as one of the units in the Sphere Originators batch, not all Summon gates have her listed as an obtainable unit. There should be a gate open right now, though, which has a boost in droprate for both her and Amadream, so you can try your hand at that.

For "Resist", I'll assume you mean mitigators - units who specialize at reducing incoming damage. There are various mitigators for different situations - offense, defense, HC management, to name a few - so it's fairly hard to say which unit is "the best", so to speak. If you're looking for pure defense, though, I'd say Wintia is your best choice - aside from providing the classic 50% mitigation, she brings in pseudo-mitigation such as Critical and Elemental Weakness Damage (EWD) nulls, a Spark damage reduction, an extra 15% damage reduction (via SP), and Guard effectivity boosts. She also boasts fairly high stats, too. Like Daltisk, she's from the Sphere Originators batch, so it'll be fairly hard to get her, but it's possible.

Vulnerability buffs are pretty much the cherry on top of a nice ice cream sundae - not needed, but nice to have. Admittedly, though, there's a good number in the community who deem it as a fairly useless buff due to their low proc chance and relatively low damage boosts, as well as due to their ineffectivity in late-game content such as Trials and Strategy Zones. If you're dead-set on finding a unit who provides these buffs, though, I'd say Ragina is your best bet. Providing EWD and Spark Vulnerability chances alongside supportive buffs like Health over Time, a Spark Damage boost, BC on Spark, a Spark Critical chance, and an EWD boost, she definitely does her job well.

As a sidenote, do know that there is a thread dedicated for questions on the wikia, called the General Help Thread. I'd suggest you post any other queries over there.

I hope this helped! (^^)/