Here, since you have to tap to use it, and you only have 6 uses, I like it with haste in Red or equipment, untaps or haste like Thousand-Year Elixir and then after it's done, a blink effect like Momentary Blink
Swiftfoot Boots can protect Purphoros or all-stars like Krenko, and Ashnod's Altar is a fine way to sacrifice tokens for extra mana for those costly curve-toppers
"Lure," limited (This creature must be blocked this turn if able.) Primary: Green Secondary: Red This is the watered-down version of Lure
It gets a ton of counters whenever we attack since each card exiled by The Tenth Doctors ability counts individually, just like the interaction between Laelia, the Blade Reforged and cascade cards
In short, this is one of those Enchantments thats going to really annoy everyone in your game, but also, youve got more mana than them, so who cares
I think you're right in that you should only be able to control one of these at a time, so planeswalk should probably include if another plane is under your control, or similar effect, otherwise you could target and steal the opponent's plane and have two