Complex sentence: The team, seeing the similarities with Zoom's powers, deduce Zoom is trying to steal Barry's speed to avoid the same fate and also realize that it was the Velocity drug that originally made Jay sick.
Split into simpler sentences: The team, seeing the similarities with Zoom's powers, deduce Zoom is trying to steal Barry's speed to avoid the same fate. They also realize that it was the Velocity drug that originally made Jay sick.