Complex sentence: Wiccan decides to help Dr. Doom and Wanda cast a spell to give the mutants back their powers, but Patriot shoots an explosive arrow to stop Dr. Doom, and ends up giving Dr. Doom Wanda's reality altering powers.
Split into simpler sentences: Wiccan decides to help Dr. Doom and Wanda cast a spell to give the mutants back their powers. However, Patriot refuses to trust Dr. Doom, and shoots an explosive arrow at him to stop the spell, which results in Dr. Doom attaining Wanda's reality altering powers.