I've seen it brought up before, but I'd like to add my support to Magic Bounce. This ability introduces a whole new element of risk; can I switch CAP into a Pokemon such as Tyranitar as it uses Stealth Rock (or Skarmory as it uses Spikes), or do I risk being hit by a super-effective STAB attack? Based on prediction, the risk is being OHKO'd by an attack, which is quite easy to achieve given CAP's typing (and we can make it frail if desired), but the reward is GREAT in preventing your opponent from setting up hazards. You can then switch something into their attack and seize the momentum from them, but only if you predict correctly. Immunity to status somewhat decreases the risk of switching in as CAP can't be hit by Thunder Wave, Toxic, Will-O-Wisp etc, but most attackers should be able to threaten CAP regardless thanks to its many weaknesses, and possible frailness. It's a very powerful option, but I think it deserves some consideration.
Other entries that I really feel maximize the risk factor are Unburden, Weak Armor, and Moxie, which would really help CAP secure a sweep, but require a lot of effort to utilize successfully.
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