The Rusty Ruin Zone boss lowers himself into a compartment in a huge statue on the NE wall with two arms. Both arms extend toward you and the NW arm will pound onto the ground. Avoid the arm itself, but jump onto the paw-shaped platform at the end of it when it hits the ground. If you don't do this immediately, watch out for the bullets the gun at the foot of the statue will fire. Avoid, at all costs, being crushed by the paw as it slams the floor. Standing on the paw as it moves back up, charge a spin dash pointing right. When the arm moves back into its highest position release the spin dash and you will hit the boss. Repeat this pattern bearing in mind that the arm that hits the ground alternates each time. When standing on the SE arm, aim your spin dash straight up. Five hits will do in this boss.