Gearlocs position themselves in starting positions according to their attack form as normal.
Then, put an HP chip in every space on the Battle Mat that doesn't have a Gearloc in it.
On a critter turn, all critters in the rolled Lane activate and simultaneously move on top of an adjacent existing critter in a different lane, making that stack of HP chips larger. If there are no adjacent critters, the critter moving is instead removed. The "simultaneous" movement is meant to prevent you from stacking the critters on top of adjacent critters in the same lane. So, if you roll Lane 1, the critters from this lane all need to move to an adjacent space in either Lane 3 (to the left) or Lane 2 (to the right).
After critters activate, one Gearloc of the party's choice activates, then critters again, then a second Gearloc, etc. The Gearlocs can go in any order, but all take a turn before any Gearloc takes a second turn.
Gearlocs use their Dex to move and Atk to attack critters on the mat, using their normal attack form. Gearlocs can't move through critters. Skills and Backup Plans cannot be used. When you attack a critter, you have to deal as much damage as HP chips in the critter stack in order to defeat it and take that HP stack as Buff HP. If you deal less damage than there are HP chips in the stack, that stack (critter) is removed and you don't get it as Buff HP.