Ok lets start with this....

Gengar wait for the Sandstorm then counter it with Sunny day before using Hypnosis on Claydol. Regardless of result end with a Fire Punch at Steelix.

Toxicroak start with a Sucker Punch at Claydol then use Role Play to steal its levitate ability and gain your own ground immunity. If Gengar manages to put Claydol under then turn on Steelix with a Cross Chop. If not then X-Scissor on Claydol.

Gengar - Sunny Day ~ Hypnosis (claydol) ~ Fire Punch (Steelix)
Toxicroak - Sucker Punch (claydol) ~ Roleplay (claydol) ~ Cross Chop (steelix)/X-Scissor (claydol)