At the time you can get zangoose (lvl 17) marshtomp is lvl 23.5, but because of the growth rate it might be feasable, however it doesnt get a fighting move until prior to gym 8, he will be faster against e4 with shadow ball, strength, brick break, swords dance. Zangoose is piss weak though and will just fail against norman, overall i think he will be slower than swampert/groudon.
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