I used Victini in my Black run and she was my favorite in-game pokemon ever. got a +Speed one on my first try, uses the gym right after to catch up to the rest of the party a bit, can get Searing Shot once you get to the move relearner (and it looks awesome)...is she actually better then Darmanitan? of course not. but showing up underlevelled for the finale, deciding to lose to the E4 a few times for exp, getting halfway through with her actually holding her own and realizing i can just finish it off now...definitely my favorite.
and the Victory Star is a perfect personality fit for your player character in B/W, imo. i dont know how spoiler-picky you are, but...
(spoilarz)
when you get Victini, an NPC tells you about Victini's victory spreading, and for most of the game winning is basically a personality trait. Cheren seems like he 'should' be beating you at least sometimes, and N's destined to fight you and was raised to use the legendary pokemon that he acquires to face you with, but you're around to win things, including things the Champion can't win. i never got this sense from any of the other games (in RBY, for example, Blue was able to exude the 'winning aura' despite not actually earning it against you. there's certainly no winning aura in RSE, Red has it in GSC even in defeat, and DPP's playable characters just seemed like relatively normal people to me.)
tldr use victini
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Leafs / Raptors / Blue Jays / TFC / Argos / Tottenham
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