A boosted uppercut or "boosted" is a movement technique that gives Jak much more horizontal momentum than the conventional intended movement techniques, making it possible to cross larger gaps. The technique has a few methods by which it can be performed, all of which yield increased horizontal momentum:
- by slowly walking off of a ledge and pressing square, cross, circle in succession before Jak begins his falling animation;
- by running along the edge of a ledge, and then pressing square, cross, circle in succession (often called a sideways boosted);
- by standing on the very edge of a ledge so that Jak's feet point downwards, and then pressing square, cross, circle in succession;
- In Jak and Daxter: The Precursor Legacy only, by zoom walking off of a ledge, then cancelling the goggles with triangle and quickly pressing square, cross, circle in succession.
The Backwards Boosted Uppercut was the first variant of the Boosted Uppercut to be discovered. Backwards Boosted Uppercuts regularly occur in casual play which makes it impossible to determine when it was first performed. A speedrunner named Meggachilly discovered the Boosted Uppercut that is still used in Jak and Daxter speedruns today.