This, as always, is a bit of a hybrid between a few different directions you could lean into depending on what you like
Many abilities of plane cards affect all players, while many others affect only the planar controller, so read each ability carefully
Its a standalone in which the TARDIS consciousness (yeah, its sentient) is trapped in a mortal vessel
Sazhs Chocobo ended up getting its own card, and it fits as the perfect one-drop on the Chocobo curve, scaling in size as the game progresses
And yes, technically you can spend your hard-earned gold buying those , but why buy packs when you can get them for free
I particularly love Ecto-1 because you could very easily combine it with a card that throws a few creatures into your graveyard and create feedback loop that makes a massive monster you can wipe out your opponents with