Lucky chant is a horrid idea. It only blocks critical hits for 5 turns, not nearly enough for most things to setup reliably.
Additionally, Garchomp @ Lum isn't anywhere near enough to sweep the battle tower, even if it can get to +6 attack. There are many pokemon with Ice/Dragon moves that will outspeed you, and Sub can only save you once. Not to mention Ice priority wrecks you.
"Paper working as intended. Nerf rock."
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