Simply because I'm too lazy to sign up for another mssg. board, here are some card idea's for you to propose: (U=Blue, R=Red, B=Black, W=White, G=Green).
Heckran UU3 Mystic 2/3
All combat damage to Heckran is reduced by 3.
Slash BU3 Mystic Legend 4/2
Double Strike
Flea RW4 Mystic Legend 2/4
Tap: Until end of turn gain control of target creature and target creature has haste.
Ozzie BBUU4 Mystic Legend 4/4
2Tap: Flip a coin. If you win the flip, remove one target opposing creature from the game. If you lose the flip, remove Ozzie from the game until end of turn.
Juggler BB3 Mystic 1/4
At the beginning of your upkeep step, choose one: Juggler is immune to all spells and abilities until end of turn OR Prevent all combat damage that would be dealt to Juggler this turn.
Spells:
Ozzie's Barrier RWGUB Enchant Creature
Prevent all damage that would be dealt to enchanted creature and instead deal it to target opposing creature.
Enchanted Creature does not untap.
Un-Lucky Cat WW2 Enchantment
Opponent loses all coin flips.
Lavos Ritual RWGUB3 Sorcery
Destroy all but one creature and one land for each player. Put the top seven cards of each players library into their graveyard. This spell cannot be countered.