Mods

Modules (Mods) are cards that can be equipped to warframes, weapons, and sentinels to enhance damage, power, survivability, speed, precepts, and utility. Mods can grant Passive Powers, Active Powers, Sentinel Precepts, and Utilities. Mods can be changed between items.

For a visual guide to mods, see the video below.

Obtaining Mods
Mods are collected in a few ways:
 * Purchasing warframes, weapons, and sentinels with platinum will give a few mods. A warframe comes with its 4 Power Mods. A Sentinel comes with 2 Precepts.
 * Making warframes via blueprint gives you all 4 power mods.
 * Survival, Spy and Capture Missions offer a mod, blueprint or consumable as a mission reward on completion.
 * Every 5 waves of Endless Defense missions will offer you a reward if you decide to exit. The rewards are random each time but tend to offer rarer mods the higher the wave you get to. As of Update 7.7, Defense mission rewards have become the main source of Rare Mods.
 * Purchasing Mod Packs from the market.
 * Dispatching enemies. It has now been confirmed that the higher level the enemy, the rarer the mod that they can drop. Though, higher level enemies do not have a higher drop rate. Mods are always dropped as level 0 mods. The type of mod will appear in the right center of the screen when a mod is picked up. Sometimes, they will be Fusion Cores (see fusion energy, below) instead of regular Mods.
 * All mods picked up from enemy drops are the same for every player.
 * Mods can be obtained from the Orokin Void canisters anywhere on the map and even more commonly from treasure rooms.
 * All mods picked up from canisters are different for every player and disappear after a length of time. With Update 9.6, mods were said to never disappear as drops but canister mods will still disappear.
 * Every enemy type has its own small drop table of mods.


 * Mod Transmutation can fuse 4 selected unranked mods to create a randomized mod, with a chance to be rare or simply more valuable.

Attributes
Mods have 5 attributes: (place on card)
 * Type: What the mod can be attached to. (Top left of description)
 * Rarity: How often a mod is dropped. (Top right of description and color of border)
 * Power cost: How much power a mod consumes from equipment. (Center right)
 * Polarity: Adjusts power cost of mods. (Top right of card)
 * Level: Mod strength. (Border, Center Left and with Rarity)

Type
Mods can only be attached to their indicated type of item. They may be generally applicable to weapons, warframes, or sentinels (i.e. “Warframe Mod”) or specific to their respective class (i.e. “Trinity Mod”). The type is listed in the top left of the description of the mod.

Mod Rarity
Mods vary in rarity as indicated by the border color and denoted in the description. Obtaining rarer mods from enemies requires fighting higher level enemies. (confirmed, higher level enemies have a higher chance to drop rare mods)
 * Bronze - Common
 * Silver - Uncommon
 * Gold - Rare

Mod Power Cost
Warframes, sentinels, and weapons have “Mod Energy.” This reflects the items ability to maintain mods while in use. Warframes and sentinels have 10 slots for mods. Weapons and sentinel weapons have 8 slots. Without an Orokin Reactor or Orokin Catalyst, they can all handle 1 energy worth of mods per level (with a maximum of 30 energy at level 30). Supercharged items (with Reactor/Catalyst) can handle 2 energy per level (with a maximum 60 energy at level 30). Aura mods can increase this capacity up to 44 (74 supercharged)

Polarity
Most equipment slots generally accept any mod. However, some slots are “polarized.” Each type of Polarization has a unique associated symbol. Putting mods of the correct polarization into a polarised slot will grant you with half the mod capacity used (rounded up) however adding mods of the wrong polarization into a polarized slot will add more mod capacity to the cost.

Mod Rank
Mods have levels ranging from 0 to as high as 10 (typically 3-5; note that this means each mod has its max level +1 in total level ups). When the level of a mod is greater than zero, it is indicated by notches in the border centered vertically on the left side of the card. Higher level mods require more mod energy.

Installing Mods
To install mods on an item, drag a mod from the collection and drop it on a Mod slot. If the Mod’s drain is less or equal to the item’s remaining Mod Energy it will install and Mod Energy will be deducted. Drain can be modified by the slot type: The item now has the benefits of the Mod.
 * Matching polarity reduces drain: Slash Dash costs 2, but dropped into Power polarized slot costs only 1. (Cost is halved for matching)
 * Conflicting polarity increases drain by a third, rounded down, with a minimum of one added: mod levels 1-5 add 1, mods 6-8 add 2 -- mods 9-11 add 3 and so on.

Bonus Stacking
To prevent exponential bonus stacking, players can't put duplicate mods in a single piece of equipment. For example, a given pistol can only have one Hornet Strike mod in it at a time.

For mods increasing shield, health or power, bonuses are calculated from the warframe's base value. This prevents exponential increases with the passive leveling bonuses introduced in Update 7.6.

Mods increasing damage or adding special damage types don't conflict with each other. Given enough mod capacity, a single weapon could have mods increasing damage and adding fire, freeze, electrical and armor piercing damage at the same time, and they would all take effect at the same time when using that weapon.

Fusion
Mods can have their overall power increased by the process called Fusion. This takes mods or Fusion Cores and combines them together to increase the overall power of a Mod.

Mod List
Warframe Mods|Warframe Rifle Mods|Rifle Shotgun Mods|Shotgun Pistol Mods|Pistol Melee Mods|Melee Sentinel Mods|Sentinel

Bugs

 * After selecting several rare level 10 cores to fuse, adding uncommon or common cores/mods may result in a decrease in the total upgrade points, lowering the final level even.
 * Uncommonly the apply fusion button will not work when fusing mods. This is temporarily fixed by coming out of the mod screen and re-entering.