| Nicolas Paradise |
Pathfinder Roleplaying Game Superscriber
This is an interesting one because size doesn't by default increase damage in 2E so one would have to decide what benefits other than reach a huge companion has and if the 2E mounted combat rules support things like overrun and trample.
Although if I could say anything for sure such a dedication should have at the very least that it grants your companion the mount trait.
Also I think there should be a minimum prerequisite of having a Savage Companion(ie large) at least if we are trying to match the 1E Mammoth rider.
That said making a homebrew mammoth rider class that starts with an animal companion that naturally grows with level could also work.