MUL-T Is by far the best proc character in ror2 when using his nail gun and power-mode. It fire 12 nails per second or 24 nails per second in power mode.

MUL-T can litterally fly with enough attack speed. If you get 8 soilder's syringes he is capable of flying on the moon. However you need ~14 syringes on the surface.

With re-tool and rebar puncher he can quickly swap tools and regain his re-bar timer. This lets him do high-bursts of damage on very quick intervals.

With 2 saws and power mode MUL-T can rival any other survivor in the game in terms of damage. He can melt most teleporter bosses in just a few seconds. He has to sacrafice range and speed but the damage is worth it.