Abahbounce

An abahbounce is a movement technique in Jak II and Jak 3 that can be used to gain much more height than conventional jumping techniques. It is performed by ground pounding onto a surface which is programmed to be slippery, but in a position where Jak can remain still such as a crack, followed by a precisely timed jump when the ground pound ends.
Tutorial
Technical
Discovery
This technique was discovered by the speedrunner Abahbob, though it is unknown when or how it was discovered.