Complex sentence: Amuro manages to activate Gundam's beam saber, which he uses to slice through the retreating Gene's suit, hitting its engine and creating a large explosion which blows a hole in the colony, which takes in Tem Ray and another engineer.
Split into simpler sentences: Amuro manages to activate Gundam's beam saber, which he uses to slice Gene's suit as it retreats. Amuro hits its engine and the resulting explosion blows a hole in the colony, which takes in Tem Ray and another engineer.