Death Toll does a lot of work for not a lot of money
As Polygon notes, The Pokmon Company has made clear that, when fans distribute art featuring any of the companys copyrighted intellectual property, they are agreeing to a royalty-free, non-exclusive, irrevocable, transferable, sub-licensable, worldwide license that gives it the right to use, transmit, copy, modify, and display Fan Art (and its derivatives) for any purpose. Legally speaking, that means TPC would have been in the clear to keep the immersive Ho-Oh as is
Runner-Up: Massacre Wurm Red With some new art from Kenta Ishikawa, everyones favorite Goblin Shaman is around and slightly more affordable
You can compare this directly to Draftsim's best commons/uncommons list for Final Fantasy and see how the Limited specialists' thoughts line up