Yxo, the Space-Time Infinity

Indestructible, Vigilance
During the beginning of your upkeep, place a 2/2 blue/black Yxo creature token onto the battlefield under your control. It has indestructible.
{t}{x}: Exile X Yxo creature tokens you control. Yxo, the Space-Time Infinity gains +X/+X until end of turn. If X is greater than 4, Yxo the Space-Time Infinity also gains flying.