it depends what it knows when it is a gabite.but some of the
strongest moves it can learn are(from best to worst):draco
meteor,dragon rush,earthquake,dragon dance,twister(good in double
battles or when you,re vs.ing a dragon type.),dragon pulse,outrage
and dragon rage(one of garchomp's WORST ATTACKS because it only
does 40 damage unless super effective or critical hit.that's it i
guess.next time!