Complex sentence: Wanting to warn his friends of Diesel's plans, Toby rings his bell to distract them, only to make Diesel 10 to destroy the sheltering they were resting in, trapping them.
Split into simpler sentences: Wanting to warn his friends of Diesel's plans, Toby rings his bell to distract them. As a result, Diesel 10 destroys the sheltering they were resting in, trapping them.