Second on this list is the incredibly rare and valuable Mega Charizard X ex Hyper Rare
Coming from the Worst Generation starter deck, Kid has a very direct effect that lets you rest three DON!!, trash a card from your hand, and set the leader as active once per turn
Its a surefire way to end games
Some are beautiful, some are terrifying
Theyre perfect for kitchen table Magic, but anywhere outside of your own playgroup is either a straight up no or a probably not. Its always best to check and make sure first in any case, but anything competitive or even vaguely non-casual is a heavy almost definitely not. Proxies arent legal in MTG in sanctioned Magic events, and depending on how theyre made, they sometimes skirt the line of legal in general
In these cases, you should absolutely play as many of the situationally powerful blue ramp and acceleration cards that make sense for your deck