I think I've used this clip for something else before, but it does show both of my favourite skills. Jack's Ice Powers and Pitch's Nightmare sand.

 

Jack has the ability to bend ice and snow to his will and can therefore do tons of cool stuff, like this here. He can also fly, I mean cmon, it's cool.

 

Pitch can create weapons out of sand, like sandy can, but he is also a shadow creature who can dissapear and appear in shadows and create shadowdances to mess with someone's head. Also epic!