4 Royal Assasin
4 Intruder Alarm
4 Root Maze
Root Maze makes the opponent's creature comes into play tapped as a static effect, then Intruder Alarm triggers to untap all creatures. In response the Assasin whacks the tapped creature, then Intruder Alarm untaps the Assasin ready for the next one.
Where you go from here is up to, you can add Tradewinds as secondary Assasins and kill by bouncing all their permanents, but then the Tradewind becomes more important than the Assasin. You can abuse Intruder Alarm with more tap-effect creatures like Prodigal Sorcerors, but then Intruder Alarm is more important than the Assasin. You can make it into a deck that can destroy all their lands as well by taking stuff like Nature's Revolt from green so you arent dependent on them having creatures. OR... you can use the Assasin to kill your own creatures... let's go White...
4 Royal Assasin
4 Intruder Alarm
4 KISMET
4 Academy Rector
3 Enduring Renewal
The Rector pulls the combo parts together, the Assasin can kill the Rector to trigger it, and the Enduring Renewal suddenly means that now we can plug any creature we want into a loop cycle of coming into play and being Assasinated only to be replayed... so then the question becomes what you want to recycle?