Complex sentence: Foghorn's plan to get back at Dawg is to roll a large snowball down the hill toward Dawg, who escapes just before the now giant snowball hits a curve and flies back at Foghorn, burying him.
Split into simpler sentences: Foghorn's plan to get back at Dawg is to roll a snowball down the hill, which gets bigger as it rolls. The now giant snowball hits a curve and flies right back at Foghorn, burying him.