Sentinels

Sentinels are companion creatures that follow their Tenno masters around and assist in various ways, depending on the precepts used to program them. It is possible to program sentinels with precepts, or skill mods, that can turn a sentinel into an attack drone or a support drone. Sentinels can also accommodate many other mods which, for the most part, function similarly to Warframe mods.

Sentinels, like weapons and Warframes, level up with affinity. They have health, shields, armor, a weapon of their own (that requires a Sentinel-specific mod driver to operate), and energy reserves. They can be targeted separately from their Tenno masters and, upon death, do not revive for the rest of the mission, unless their master dies and spends a Revive. Enemies tend to target a Warframe first, but may often target the sentinel instead.

Sentinels come along their own weapons, taking two of eight sentinel slots (which are different from warframe and weapon slots). All Sentinels will come with two mods specific to their type installed at creation. Sentinels have four polarity slots, an Orokin Reactor upgrade slot, and can be Polarized with a Forma.

Cosmetics can be applied to sentinels, but currently serve no functional purpose.

Sentinel Experience

 * Main Article: Sentinel Experience

Sentinel Weapons
As of Update 10, Sentinel's can now equip other sentinel's weapons, for example, Wyrm can equip Carrier's Sweeper instead of its usual Laser Rifle. However, the only way to get another sentinel's weapon is to craft that particular sentinel to retrieve their specific weapon.

Sentinel Mods
There are exclusive Sentinel Mods for each Sentinel. Only Shade can use the mods Ghost and Revenge, Wyrm has Crowd Dispersion and Warrior, Dethcube has Swift Deth and Vaporize, Carrier has Vacuum and Striker, and Djinn has Thumper and Fatal Attraction. There are 10 precept mods slots and 9 possible mods for those slots.

All sentinel weapons have unlimited ammo, 0% crit chance and never "reload". There is currently no benefit whatsoever to giving them any mods related to crit chance, crit damage or magazine capacity. Mods that affect the rate of fire, base damage, multishot or add elemental damage all work like on normal weapons of the same type. Reload speed effects the cooldown, or pause, between shots fired by Shade's burst laser pistol or Wyrm's laser rifle.

Sentinel AI
Sentinels will use their precepts in a prioritized order, where the top left slot is the highest priority and the bottom right slot is the lowest. Precept mods do not need to be installed in the respective polarized slot to be used. Also, while the Arsenal UI only shows the first 4 precepts installed, a Sentinel will still use other precepts if they are installed.

Sentinels will check to see if the conditions to use the highest priority precept are fulfilled, and will continue to use that precept until the conditions are no longer met. Then they will check each other precept in priority order. Sentinels will also interrupt the usage of lower priority precepts to use higher priority precepts.

Tips

 * A basic build for your Sentinel is as follows:
 * Ghost, Crowd Dispersion, Guardian or Sanctuary should go in the highest priority slot.
 * Regen should go in the next highest priority slot.
 * Vaporize, Vacuum Fatal Attraction or Crowd Dispersion/Ghost (if the highest priority slot was taken) should go in the next highest priority slot.
 * Swift Deth, Warrior, Sweeper, Striker or Revenge should go in the next highest priority slot.
 * Coolant Leak should go in the lowest priority slot.

Acquisition
Sentinels (excluding Djinn) can be bought for and the blueprints for.