Grineer

"From the chaos of the Collapse, they emerged, Violent hordes of decaying clones, overflowing from their toxic womb. They flood the Origin System, swallowing colonies whole. The twin Queens, the SISTERS, have devised a plan to transform the scattered colonies into an Empire across the planets. The Sisters have sent their most trusted brood on a vital quest - the TENNO, hidden and asleep, must never awake."

- In-game Lore Description

The Grineer are the first enemies encountered by newly reawakened Tenno. They utilize technologically crude but undeniably effective weapons. More than one Tenno has fallen because they underestimated the accuracy of a Grineer Lancer with their Grakata rifles while waiting for shields to recharge.

To a man, the Grineer are a race of clones; products of ancient, half-remembered technologies. Copies of copies, Grineer are produced in industrial quantities, and all Grineer are genetically defective, their genome damaged by the invasive cloning procedures used to birth each generation. However, these defects are as mass-produced as the Grineer themselves, allowing for the rapid standardization of techno-augmetic adaptation between such generations. Indeed, it could be argued that the Grineer are better at fixing broken bodies than they are at making ones that function to begin with. Their homeworld is a polluted, ecologically ruined Earth. They are people acting on an ultimate xenophobia, fueled by hereditary psychoses, and a burning hate of anything and anyone not like themselves. In the end, should they succeed, there will only be Grineer left alive in the solar system.

It is said that the Grineer, although at the height of their power, must use advanced technology as a crutch against their degenerating bodies, most of which comes from the Corpus, regardless of the fact they actively invade their territories. It is reasonable to assume if the Corpus simply denied access to more technology to the warring Grineer, they would quickly lose strength as they have little means to replicate such advanced tech. However, as famously quoted by Alad V, "Profit numbs the feeling". That is to say, that even though the Grineer battle them, losing their primary customer would not be an option.

In battle, the Grineer use heavy armor coupled with attrition and ambush tactics. While they are fairly weak individually, they are a potent threat in groups, able to lay down withering streams of fire at all ranges from behind cover. Specialty troops use more advanced weapons, and many are even issued comparatively advanced reactive armor to give them an edge.

The armor on the average Grineer deserves special mention because it makes them the faction with the highest resistance to damage. This coupled with several elemental resistances and the fact that the relatively common Elite Lancer is heavily armored makes them the most durable faction, with their Medium and Heavy units becoming absolute bullet sponges at higher levels.

Enemies
Grineer have a dual classification system. Primarily, they are classified by their armor class - Light, Medium, and Heavy - which describe their base armor and their shared damage multipliers. Secondarily, they are classified by their role or engagement style. Infantry use rifles and shotguns and tend to find good cover and engage at medium to close range. Special Weapons units use non-standard weapons (ex: rocket launchers, miter, snares, etc.) and typically have various roles in combat based on their loadout. Finally, Brawlers engage at close range and use primarily melee weapons.

Light
Light Grineer units are melee units with decent damage with low durability. Some of them have special features. Butcher=


 * -|Flameblade=


 * -|Powerfist=


 * -|Scorpion=


 * -|Shield Lancer=

Medium
Medium troops make up the bulk of the Grineer army. They are not particularly dangerous when alone, but in groups they can pose a serious threat. Ballista=


 * -|Elite Lancer=


 * -|Eviscerator=


 * -|Hellion=


 * -|Lancer=


 * -|Scorch=


 * -|Seeker=


 * -|Trooper=

Heavy
These units are the strongest and toughest of the Grineer. Apart from the Grineer Commander, these units don't take advantage of cover. Heavy Grineer cannot seem to retaliate while under attack, showing a vulnerability to status effects; therefore it is possible to dispatch lone Heavy units easily with sustained firepower. Most Heavy units have significant base Health and armor. Bombard=


 * -|Commander=


 * -|Heavy Gunner=


 * -|Napalm=

Utility
The utility enemies of the Grineer are dangerous in their own right, such as the Roller, one of the most infamously annoying enemies in the game.
 * -|Latcher=


 * -|Roller=


 * -|Regulator=


 * -|Sensor Bar=


 * -|Broken Light=


 * -|Target=

Bosses
Bosses are officers within the Grineer faction. Capt. Vor=


 * -|Councilor Vay Hek=


 * -|Gen. Sargas Ruk=


 * -|Kela De Thaym=


 * -|Lt. Lech Kril=


 * -|Tyl Regor=

Trivia

 * Before Update 10 was implemented, the Grineer troops used to speak fluently in English, this was then changed to Grineer language in order to retain the lore of Grineer with aggressive dislike to foreign races.
 * One of the more infamous voice lines from pre-Update 10 Grineer was "Combat formation Bravo!". It was jokingly explained by a DE staff member that a key requirement of Formation Bravo is to never mention anyone's mother. Other joking fan interpretations of Formation Bravo refer to the "enemy tower" bug.
 * Other popular lines from pre-Update 10 were "Stay close to the walls.", "Hey, leave my mother out of this." and "Kill em!".
 * So far, the Grineer is the only voiced faction to have a strong direct aggression against the Tenno, speaking their name during their attacks in their language.
 * They also have been heard saying Wafram, as in Warframe, when spotting one themselves.
 * When playing an Invasion mission, while the player has sided with the Grineer, they still will cry out quotes like Tenno Scum, because although the AI is allied with the player the voice choices still don't alter. The same goes with Shadow Grineer, shouting at other Grineer the same anti-Tenno aggressive lines.
 * The Corpus nicknames the Grineer as the "dogs", not because of their degraded appearances but to their aspect of extreme servitude towards their leaders (and possibly creators), the Twin Queens. This was mentioned by Alad V during The Gradivus Dilemma.
 * Their name "Grineer" seems to be a portmanteau of the words "Genetically"  and "Reengineer" which makes sense given the lore behind them.