It's a thing in practically every TCG, but Pokemon is often much more influenced by it as people try and get their hands on their favorite trainers
A card in mint or near-mint condition is significantly more valuable than one with scratches, whitening, or bends
This is because whenever a nonland permanent an opponent owns enters the battlefield under your control, that player loses life equal to its mana value
Proxy King cards are made on premium German black-core playing-card stock with direct printing (we never use sticker overlays) and standard MTG sizing , so they sleeve and shuffle cleanly and feel consistent across a full deck
In addition to these Time Lords, there is the Master
Yes, Crumble and Oxidize only hit artifacts and not enchantments, but I feel the amount of artifacts that see play now versus several years ago has gone up a lot