one move ends Trick Room Shuckle with Power Trick:
it hits x2 on Shuckles Rock Type, and will always hit Shuckle first. And Shuckle has Terrible HP stats.
and as a Staller, Shuckle needs
Shuckle @ Leftovers
Impish (Def)/Careful (SDef) Nature
252 Def or SDef/ 160 Def or SDef/ 36 HP
- Double Team