MTG Pioneer Challenger Deck 2021
Pioneer—a new nonrotating format featuring cards from Return to Ravnica and forward
Pioneer is a constructed format and therefore adheres to the following constructed rules:
With the exception of basic lands (Plains, Island, Swamp, Mountain, Forest, and Wastes), your combined deck and sideboard may not contain more than four of any individual card, counted by its English card title equivalent.
All Standard releases from Return to Ravnica forward are legal