The Ninja Epidemic

You stand back and wait for him to make the first move. After a little stare down he jabs forward with a sword thrust which is avoided easily enough by your dexterious movements. You counter the attack with your sais and they puncture the ninjas chest to leave two gaping holes in thier wake. The ninjas eyes widen in shock before he falls dead to the ground.

You stare the remaining eight ninjas and they stare right back. Four of them exchange glances and drop something from thier hands which explode into plumes of smoke.

When the smoke clears, only four ninjas remain. And they are angry looking ninjas. They no longer take the one-at-a-time approach, and they all step in to attack you. Two before you and two behind.