For one thing Icicle spear has 25 base power so 25 X 5 would equal to 125 so it is very nice. Also if you take in account of STAB, it would become 187.5 base damage already. With the new Shell Break, cloyster instantly increases 2 stages in ATK, S.ATK and SPE but also lowers DEF and S.DEF.
Cinccino is also a great user if you don't want to use Cloyster(why?!?!?)Cinccno has skill link too and has Bullet seed, Rock blast and Tail slap(has STAB)
Ambipom is the final user with Skill link. It has Fury swipes and fury swipers has 18 base power so 18 X 5 would be 90 plus STAB would be 135.