(Picked randomly)
You and your rival play in turns
They give you mana - the games energy - and are played, not cast
For example, many Avatar cards get stronger as you cast lesson spells, like Katara, Seeking Revenge or Sokka, Bold Boomeranger, and other cards care about having lesson cards in your graveyard
It does in fact qualify, though it obviously cant be force-transformed with Tetzin, Gnome Champion or through any other means than melding it with Urza, Lord Protector or Mishra, Claimed by Gix
With every new set come exciting new legendary creatures, and Dungeons & Dragons: Adventures in the Forgotten Realms doesnt disappoint