De-activate the Precursor blockers was a mission in The Precursor Legacy that Jak and Daxter completed to obtain a power cell. Several active Precursor blockers were found in Snowy Mountain until Jak deactivated them all and found a power cell.
In Snowy Mountain there are thirteen Precursor blockers located throughout the level. These have to be deactivated for this mission. The last one will reveal a power cell. To deactivate a Precursor blocker you will need to properly time a double jump or high jump to get over the shield surrounding it and land on the button on top.
The locations of all the Precursor blockers are as follows:
- 1/13 - At the start of the level, when you exit the gondola.
Go forwards past the gap and take a left.
- 2-3/13 - Two more are in a small pass with the multitude of snowballs rolling down it.
Return a bit and instead of going left, go straight ahead through the ice cave until you reach an ice lake.
- 4-7/13 - There are four more here, one in the center and the others surrounding it.
Take the frozen slope here and you will reach the lurker fort area.
- 8-10/13 - Nearby (to the right of the fort) is another blocker, then circle around the fort to find another two.
From here take the nearby frozen bridge and cross it.
- 10-12/13 - There are two here with some lurkers on a slippery plateau.
Cross the next bridge as well.
- 13/13 - The last blocker is here, in front of the cave entrance. Deactivate it and a power cell will pop out.
Due to the slippery ice on Snow Mountain, some blockers are very hard to jump on accurately, as you will find it hard to time a jump while sliding in an odd direction. In addition, if a blocker rebuffs Jak it will send him back a few yards, requiring a longer distance to be traveled over the slippery ice to return to the blocker. It is suggested to try to find a patch of soft snow or a perch to start off, then try to accurately jump in the center of the force field to deactivate the blocker. If this is impossible (which will be the case in a few instances) then you must carefully build up momentum from sliding in a single direction, and time your jump accurately to reach the center.