Both players share a resource feature ranging from 0-10 on your side, and 0-10 for your opponent (essentially 0 to -10 from your perspective)
Just paying 4 mana to copy the strongest token around (populate, if you will) is very good, and lots of cards and commanders can give you a token every turn, meaning that this class will draw you a bunch of cards even on your opponents turns
Maro's story of where that card came from
Queen Allenal of Ruadach's first ability counts itself, so its power and toughness will always be at least 1/1
She also appears in Pokemon Ultra Sun & Ultra Moon, Pokemon Let's Go Eevee, and Pokemon Let's Go Pikachu, and even makes multiple appearances in Pokemon Masters EX, along with her partners, Granbull and Tapu Fini
Legality depends on the tournament format -- Mondrak, Glory Dominus can be legal in some formats and banned or restricted in others