The main problem for kisame is that samehada can't absob the shockwaves from Deidara's explosions. Furthermore, Doton>>Suiton so he has the elemental advantage. Further,Samaheda seems to dislike extreme heat as well.Deidara takes this mid-high diff IMO. Kisame's Kenjutsu is useless, and his shark projectiles can probably be dodged. However, Samehada can sense C4 molecules, I believe.