Dragon Math

Dragonomy —Dragon spells may be cast using mana of any color.
Whenever a non-token Dragon enters the battlefield, create a token that is a copy of it, except the token isn't legendary if that Dragon is legendary.

Whenever a non-token Dragon is put into the graveyard, return it to the battlefield tapped with a rebirth counter on it.

Whenever a counter is placed on a Dragon, create a Gold token.