Charger

Chargers are quadrupedal abominations resembling canines made from Grineer (perhaps Lancers) that almost always hunt in packs. They will quickly and repeatedly claw at players once in range, and their attacks have a chance to stun on hit.

When using heavy melee weapons (i.e. Fragor) rapidly pressing the melee command makes the animation unable to be interrupted by runners and chargers. It is unknown whether or not this is a bug.

"Fast with weak claw attacks" (as stated in-game) is an understatement as a small group of level 20 chargers can rip through your shields in just a few seconds. At level 40+ 100 or more of your shield can be depleted with each fast strike of their claws.

Infested Chargers seem to have drastically altered the bodies of their unlucky hosts, with only their head and right arm to be in their original places, with the left arm pushed down to be used as a hind leg, a leg stripped of flesh almost entirely and used as a front leg, the right arm pushed back and replaced with another front leg, and the bones of the rib cage are pushed through the heavy armor of the belly region to form crude scales. Note however, that along the region of the neck, a fleshy 'Jaw' petrudes from the area, better seen on Phorid  where it is larger and more visible. This may resemble the new "head" the infection has formed for the host body.