You’ll need: Army men, cotton swabs, drinking straws.
Divide your group into two or more smaller groups, giving each an adequate number of straws, a box of Q-tips, and a set of plastic army men (or farm animals, jungle animals, etc…).
Allow teams to set up their men on a table on opposite sides of a room, and at the given signal, to commence firing upon their opponents soldiers in blowgun fashion, using the Q-tips and straws. Straws can be recycled during the battle. The army men are fairly difficult to hit with any accuracy, which allows for a good length of play time, as well as lots of attacks launched at people instead of army men. Establish your own rules about who can retrieve the Q-tips from the center of the “militarized zone”.
A safe game, and easy clean-up, and everyone wins!