The Face, but with legs. It has 1/2 the stats The Face has, but 25 times as much speed. Somewhat similar to Shy Boy, but drops as much money as The Face upon death and has one more knockback than Shy Boy.
The best way to defeat it is to treat it as if it was a Shy Boy, but without any specific Red/Floating weaknesses. Since it is Traitless, Leggsy has fewer crowd-controllers and debuffs that can slow its progress. Instead, use plenty of meatshields, and if that isn't enough, weaken it with Thaumaturge Cat.
When its running and chomping is put to an end, Leggsy will drop as much cash as an ordinary The Face does, so don't be afraid to use a lot of your budget to kill it. Although, this is not that possible in Floor 18, where you will probably be tight on cash until you kill the first or second Leggsy.
600 damage (947 DPS)
170 (Area Attack)
19f (0.63 seconds)
12f 0.4s (7f 0.23s backswing)
*In each stage, there is strength magnification, the value of health and attack power varies due to this value.