Complex sentence: Quicksilver first thought he should be leader though, though he is captured by the Mole Man on the first mission he is rescued by the Avengers, who defeat the Minotaur without him, and would sometimes quarrel with the other members.
Split into simpler sentences: Quicksilver first thought he should be leader, though he is captured by the Mole Man on the first mission. He is rescued by the Avengers, who defeat the Minotaur without him, and would sometimes quarrel with the other members.