If you attack with your “UFO Turtle” and it is destroyed as a result of battle, you may attack with the monster Special Summoned by “UFO Turtle” before entering Main Phase 2.
If your opponent controls your “UFO Turtle” and it is destroyed as a result of battle, you get the effect of “UFO Turtle” NOT your opponent.
Since the Special Summoning occurs during the Damage Step, “Torrential Tribute”, etc. cannot be used.