Collisions (my most memorable game was an assault where base defence was the legged cicada colliding the cheetah to smithereens, both were unarmed/ammo depleted);
knockdown;
melee;
hatchets;
srm locks;
no overheat self-destruction;
overheat ammo explosion;
overheat slow-down;
overheat torso and arm slow-down (heat compromises aiming);
etc.
Next to "do you want: NA, Euro, Oceanic", there would be a switch asking whether you also want to go hardcore mode.
EDIT: exchanged "overheat aim shake (like jump aim shake)" for "overheat torso and arm slow-down"
Edited by AbsUserName, 08 November 2015 - 04:46 PM.