>>36541387In doubles you can make Regigigas an absolute monster by pairing it with Gourgeist. Gourgeist is just slightly faster than Gigas, so first turn have it Z-Trick or Treat on Gigas to make it Normal/Ghost and raise all of Gourgeist's stats. On the same turn, Gigas uses Psyche Up on Gourgeist to gain the stats. Gigas is now resistant or neutral to everything but dark, and has huge bulk thanks to the stat boosts. If the opponent switched into a fighting type to deal with it, they now have to lose another turn switching out again, and if Gourgeist survives another turn it can Skill Swap Slow Start off.