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Proposed Canon

A non-humanoid mount unit - eight legs, poisonous bite, spins webs ... suffers from the same pwoblem^[1] as the dwagons.

Speculation

Known Users

Gobwin Knob - apparently their main source of non-flying mounts^[2][3][4] and the common steeds of the Knights in Stanley's Service^[5][6].

Can also be used on their own, without a rider.^[7]