According to the description, the Kinetic Strike Module lets Mecs punch stuff and increases mobility. What exactly are the effects? Is the number of uses limited in some way? How much damage does it deal? Do I need to be adjacent to an enemy to use it? How much is mobility improved?
Usage, Damage & Effects
The Kinetic Strike does 12 guaranteed damage to an adjacent unit. This can be upgraded to 18 by a Foundry project. Note that only the 4 squares that share sides with the MEC's square are considered adjacent - not diagonal squares. If an enemy is in an adjacent square but the other side of a wall, the attack will punch through the wall to hit them, destroying the wall in the process.
Enemies fly backwards a substantial distance from the force of the punch if they die, and they destroy any cover that they hit. If the target is thrown into another enemy, this does not hurt the second enemy. However, it can destroy their cover, and if the target hits a car or other explosive then they will set it off.
If Kinetic Strike is used to kill a Mechtoid or a Muton Beserker, instead of the usual animation we see our MEC grapple with the enemy briefly, and the enemy may not be thrown backwards. This can cause damage to objects to the side of the target.
Kinetic Strike can also be free-aimed in any of the four grid-aligned directions. This may be useful for destroying cover, or for attacking an enemy that the player knows about but does not have line of sight to. Additionally, a free-aimed punch can destroy the power conduits in the final Slingshot mission (pointless but fun :-)).
Implementation & movement increase
Kinetic Strike has an unlimited number of uses, and no cooldown. It can be used when the main weapon has no ammunition. If the damage increase foundry project has been completed, MECs can use Kinetic Strike twice in one turn instead of moving.
The module appears to increase the distance that a MEC can move on a single action point by 3 squares. Specifically, a level 1 flamethrower-equipped MEC can move 7 squares on its first action, and a level 1 kinetic strike equipped MEC can move 10 squares. This movement increase may sometimes be a more important effect than the punch itself...