There should be a variety of pins that you can get as an upgrade and you can get upgrade for them(1,000 butt coins for each type)
Ex: Explosive pins: after hitting someone, it hits everyone else in a 2-block radius. Freeze pin: after hitting someone, freezes everyone in a 1-block radius. Poison pins: has a liger effect on the ground it lands on for a 4-block radius and 5 seconds.