Blaze Black & Volt White walkthrough
12 parts, one per checkpoint Blaze Black & Volt White’s own documentation defines: the areas each one opens, the wild Pokémon and trainers in them, and the fight at the end of it. Everything here is read off the game’s own files, so anything it doesn’t state isn’t claimed.
Part 1: Just started (no badges)
6 areas · 27 trainers · Rival Bianca (Snivy), Rival Bianca (Oshawott), Rival Bianca (Tepig) and 21 more
Part 2: 1 badge — Trio (Striaton)
7 areas · 27 trainers · Rival Cheren (with Snivy), Rival Cheren (with Oshawott), Rival Cheren (with Tepig) and 2 more
Part 3: 2 badges — Basic (Lenora, Nacrene)
7 areas · 43 trainers · Game Freak Morimoto, Burgh, Rival Bianca (Snivy) and 2 more
Part 4: 3 badges — Insect (Burgh, Castelia)
12 areas · 41 trainers · Rival Cheren (with Snivy), Rival Cheren (with Oshawott), Rival Cheren (with Tepig) and 2 more
Part 5: 4 badges — Bolt (Elesa, Nimbasa)
6 areas · 40 trainers · Rival Cheren (with Snivy), Rival Cheren (with Oshawott), Rival Cheren (with Tepig) and 3 more
Part 6: 5 badges — Quake (Clay, Driftveil)
8 areas · 29 trainers · Pkmn Trainer N
Part 7: 6 badges — Jet (Skyla, Mistralton)
9 areas · 36 trainers · Rival Cheren (with Snivy), Rival Cheren (with Oshawott), Rival Cheren (with Tepig)
Part 8: Twist Mountain · Surf usable
3 areas · 2 trainers
Part 9: 7 badges — Freeze (Brycen, Icirrus)
14 areas · 53 trainers · Brycen, Rival Bianca (Snivy), Rival Bianca (Oshawott) and 3 more
Part 10: 8 badges — Legend (Drayden / Iris, Opelucid)
8 areas · 24 trainers · Rival Cheren (with Snivy), Rival Cheren (with Oshawott), Rival Cheren (with Tepig) and 5 more
Part 11: Champion — eastern Unova opens up
27 areas · 12 trainers · Cilan, Cress, Chili and 9 more
Part 12: Route 18 · Waterfall usable
3 areas · 10 trainers
This game's documentation doesn't say where 11 of its 355 fights happen, so those trainers are on no part of this walkthrough; they are all on the Trainers page.