MKDasher made quite a few ports of retro tracks from other types of Mario Kart early in the history of Custom Track development. He held the world record for SNES Ghost Valley 2 and currently holds several other world records on Mario Kart DS. He also does tool-assisted speedruns (TAS) of various games.
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DS Airship Fortress — DS Dokan Course — DS Waluigi Pinball — GBA Rainbow Road — GBA Sky Garden — GCN Daisy Cruiser — GCN Rainbow Road — GCN Wario Colosseum
N64 Yoshi Valley — SNES Bowser Castle 2 — SNES Mario Circuit 1