Slowpoke93% => Slowbro or Sowking?

Slowking has worse movepool for defense (one-bars). Except for that they're identical.

i personally use confusion + ice beam slowbros as defenders

my slowbro usually cast 2 ice beam/fight
i guess slowking with blizzard could do the job

but im not sure if slowking always have chance to use blizzard? is there any pokemon that can kill it so fast?

also its better make opponent dodge twice per fight rather than once, in my opinion.

also someone mentioned that fire blast is unwanted move, so you might get that if you evolve good IV slowpoke into slowking

i prefer ice moves for type coverage vs grass types and also coverage vs dragonites

Well, fire gives coverage against grass as well, and also (unlike ice moves) is double super effective against Scizor (Scizor's X-Scissor charge move is super effective on Slowbro/Slowking).