In late 2019, Wizards of the Coast announced the creation of a new format called Pioneer. Pioneer took inspiration from the player-created format Frontier, which was designed as a cheap and convenient format for players who wanted to use their rotated Standard cards. Frontier encompassed sets between Magic 2015 and onward, using the M15 frame as a reference for legality. In this way, it was similar to Modern, which uses an earlier change of card frames as its cutoff point.

High Quality Magic the Gathering Proxy MTG Proxy MTG Card.
Made by German Black core paper, printed by Heidelberg Printer,
which makes it the same thickness and feel as a real Magic card.
These are great proxies for casual play or FNM tournament play.
Once double sleeved will be hard to tell the difference from a real Magic card!

Email seller cardmire_printer@outlook.com for any questions.
And this is the purchase link:
https://pkmtg.com/