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you could probably add an OO sections to your rmt because the redundancy between chomp / ttar / lando lets you change their sets to pick and choose weaknesses. scarfchomp+sr helm lando = better vs volc, cb dragons, sd scizor but loses the fast pivot and rotom-w killer, etc.
SUPERIOR DRAGON GEM CHOMP (chain) / cbtar / scarf lando-t / ferro / zam / latios
3 atks sd yache chomp / sr tar / scarf lando / ferro / zam / latios
scarfchomp / mixtar / sr helm lando / ferro / zam / latios
are probably the relevant ones unless u wanna start going full zf and use gravity / explosion normal gem / smack down sd lando-t