Miirym, Sentinel Wyrm 
Legendary Creature — Dragon Spirit
Flying, ward 
Whenever another nontoken Dragon you control enters, create a token that's a copy of it, except the token isn't legendary.
Legality
standardNOT LEGALpioneerNOT LEGALmodernNOT LEGALlegacyLEGALvintageLEGALcommanderLEGAL