My first thought was to use Blue, Trickster Mage, Opposition, Hoodwink... That sort of thing.
Maybe some artifact mana like Star compass Sky Diamonds, Cameo...
Also rhystic spells, and some creatures like Gulf squid, Jolting Merfolk and/or stuff like Ribbon Snake where You have to pay 2 to keep it from flying .
Maybe splash white, like LotusMox said "creatures that don't tap to attack".
What do You think?