Complex sentence: In spite of help from Huey, Dewey and Louie, the situation looks desperate for Donald Duck, until his fist accidentally connects with Pete's jaw, which crumbles--it turns out Pegleg Pete literally had a glass jaw.
Split into simpler sentences: In spite of help from Huey, Dewey and Louie, the situation looks desperate for Donald Duck, until his fist accidentally connects with Pete's jaw, which crumbles. Tt turns out Pegleg Pete literally had a glass jaw.