Vedalken Spy-Mage 2U
Creature - Vedalken Rogue Wizard
Whenever Vedalken Spy-Mage deals combat damage to an opponent, fateseal that much. U: Vedalken Spy-Mage gets -1/-0 and is unblockable until end of turn.
Unstable Bridge 3
Whenever one or more creatures attack, if the total power of attacking creatures without flying is 7 or greater, tap all attacking creatures without flying and remove them from combat.
Infinity Threshold 5GG
When Infinity Threshold enters the battlefield, put a 1/1 green Saproling creature token onto the battlefield.
Whenever you cast a spell, for each Saproling creature you control, put a 1/1 green Saproling creature token onto the battlefield.
(number of tokens tends to infinity, though never quite reaches it, unless you have Sprout Swarm or something like that... The word "infinity" has a special meaning in my set, which is why I went this flavor route.)
When Segregation enters the battlefield, exile target creature.
Creatures that share a creature type with the exiled card get -1/-1.
When Segregation leaves the battlefield, return the exiled card to the battlefield under its owner's control.