If you name a mob ".ghast," any mob will grow to the size of a ghast! An armadillo will puff up its body to several blocks! Wardens and Pillagers become giant, but with tiny heads like GigaChad. You can name not just mobs, but all entities. For example, an armor stand will get huge, and any item it's holding will be ridiculously big. I think you could use a mace the size of a player to take down the Ender Dragon in one hit! The breeze will fly right out of the whirlwind. And what about the ghast itself? It grows to titanic sizes! To make these name tags work, set up a command block and enter the code I left in the comments.