Reverse Flight

"More of a straight quality of life, Ace has gained a new special toggle button to allow it to turn back and fly in reverse on any selected flight pattern. [...]"

- Ninja Kiwi, referring to Version 30.0 Ace buffs

Reverse Flight is a targeting option in Bloons TD 6, available for the Monkey Ace starting from Version 30.0. It reverses the flight direction of the Monkey Ace, similarly to Change Hands for the Boomerang Monkey. However, to avoid locking the Ace into the same location, the Reverse Flight option has a cooldown of 5 seconds per Ace.

Summary
In locations where the Ace benefits better going against the grain, or just to go backwards in the direction it came, this targeting option comes very handy.