It's like unbreakable! [Dipper throws his arms up in the air as he says it, almost hitting Mabel in the face.] I threw stuff at it!

[He thinks it's actually a pretty great power and also that it's pretty cool she has a shield-ey power like his teke. They match while both still having their own particular version of shield-ey powers.]

Also when it hits stuff, it all sort of violently bounces off so she can run people down in a giant roll-ey rampage.