mtg cards with x Rules Text: damage, Type: Sorcery, Instant, Colors: Red, 98 put a +1/+1 counter on that creature and a +1/+1 counter on X Rules Text: additional cost, X,

Revival Trance, does reanimation and basically punishes opponents for spending cards to kill its creatures

Path of Discovery

It requires a touch of political finesse to assure it comes back your way a great bargain would be trading it to the player whos falling behind but it adds interest to the board state and often sparks interesting deals that you wouldn't get otherwise

Improvise lets you tap your artifacts to pay for generic mana costs, making it so you only need to use colored mana from permanents to cast spells

Grubs Command Grub's Command does a bunch of things that youd want, although only at sorcery speed