Riven Mods

Riven Mods are special mods that can feature up to four different stats, sometimes disadvantageous. Riven mods are unique in that their stats are heavily randomized, allowing for a significant variance in mod effectiveness, and because the type of Riven mod acquired is kept hidden from the player until they complete an assigned challenge for the mod. Riven mods are also exclusive to certain individual weapons, with each mod having only a single weapon associated with them. Currently, Riven mods are limited to Shotguns, Secondary weapons, Assault Rifles, Bows, Launchers, and Sniper Rifles, as well as any Sentinel weapons that fall in the aforementioned categories.

A single Riven Mod is given to players upon completion of The War Within quest, and additional Riven Mods can be acquired as rewards from Sorties.

Upgrade and Trading costs of Riven mods are equivalent to those of Rare mods.

Challenges
When a player receives a Riven Mod, the nature of the mod itself is hidden from the player, a state referred to as being Veiled. In order to unlock the mod's type and effect, players must complete a challenge associated with that mod, for example, killing a certain number of enemies without being afflicted by Status Effects. In order for the challenge to be registered, the Riven mod must be equipped on a weapon that the player will be carrying into a mission. Riven mods that have not been unlocked will consume no mod capacity when equipped on a weapon, but will not confer any bonuses either. While Riven mods must be equipped on the weapon it is assigned to (e.g. Pistol Riven Mods can only be equipped on secondaries), it is possible to complete the challenges using any weapon.

If a player manages to complete the challenge, the Riven mod's type and stats will be revealed after the leaving the mission, regardless of whether the mission is successfully completed, aborted, or failed.

The challenge difficulty depends on the mastery rank of the mod; e.g. a Rank 8 Riven mod will have a lower difficulty than a rank 12.

Stats
Unlike other mods, a Riven mod has randomized values for their various stats, i.e. two of the same Riven Mod can have different numbers for their effects, along with a random Polarity and Mastery Rank requirement. Each Riven mod can have from two up to four stats associated with it: two or three beneficial effects, and possibly one counterbalancing negative effect similar in concept to Corrupted Mods. Both of these aspects mean that Riven mods are unpredictable, but at the same time their randomized positive effects have the potential to feature significantly higher values than standard mods. It is possible to receive a Riven mod that has high positive stats without any drawbacks, though the opposite is also possible.

Riven mods have unique, systematic names, consisting of a prefix, a core and suffix, following "Prefix-CoreSuffix" or just "CoreSuffix" (as in Latron Deci-puratron, or Karak Satitox). Prefixes and cores draw from the same name pool. There are 24 unique, randomisable stats and therefore 24 prefixes/cores and 24 suffixes. It should be noted that negative effects are not represented by the name. The prefix and suffix cannot be of the same stat, (such as Braton Visiata), and it is possible to get stats for weapons who cannot take advantage of them (such as Miter Critatis).

The 24 positive stats are:

Disposition
The randomized stats for Riven mods are affected by a variable known as Disposition, a modifier that collates the usage popularity of a given weapon across the entire player base, and then adjusts the resulting random stats to better fit that weapon. There are three different ranks of Disposition that can be assigned:


 * Strong: This Disposition is assigned to infrequently used or unpopular weapons, which will result in Riven mods for said weapon receiving more powerful potential stats.
 * Neutral: Weapons that see average usage within the player base, resulting in equally average ranges of Riven mod stats.
 * Faint: Assigned to popular weapons that see frequent usage, this Disposition creates Riven mods with more restrained stats.

A weapon's Disposition can be seen in the Arsenal under the Upgrade tab.

Below is a list of weapons by Disposition:

All Weapons=
 * -|Rifles=
 * -|Shotguns=
 * -|Secondaries=
 * -|Sentinel=

Cycling (Re-Rolling)
Another unique aspect of a Riven mod's stats is their ability to Cycle (re-roll) the mod stats and/or polarity, via the Cycle function in the Mods segment in the Orbiter by spending Kuva, a resource found through Kuva Siphon objectives in high level Grineer missions. Cycling a Riven mod will randomly reroll the mod's stats, which can result in either better or worse stats or effects for the mod, though this will not change the weapon that the mod is assigned to first. Both the stats themselves and the percentages for the stats are changed when cycling a Riven mod, though the mod's polarity and Mastery Rank requirement will not.

After cycling a mod, both the old version of the mod and the new version is displayed, and players can choose whether to accept the new stats, or revert to the old version. Regardless of the player's choice, the Kuva spent in cycling the mod will not be refunded.

The minimum cost for Cycling a Riven mod is 900 Kuva for the first cycle, with increasing costs on subsequent cycles of the same mod. Cycle cost is capped at 3500 Kuva.

Putting ranks into a Riven mod and then re-rolling does not reset any ranks previously put into the mod, i.e. a rank 4 Riven mod that is cycled will retain its rank 4 status.

Players can see whether a mod has been cycled by a circular arrow icon at the bottom right of the Riven Mod, which will also display a number indicating how many times the mod has been cycled.

Limitations
Unusually for mods, Riven mods are Mastery Rank locked, with different mods requiring players to be of a certain Mastery Rank to be able to use them. Also, each type of Riven Mod is exclusive to a particular individual weapon or its variation, and a weapon can only have one Riven mod equipped at any time. A player can is limited to 15 Riven Mods in their inventory at a given time. The player can purchase additional Riven Mod slots from the Market at for a set of 3 slots, allowing up to 60 Rivens at any given time.

Trivia

 * Riven mods feature a dynamic image, which constantly shifts between the images of the bonuses. For example, a Riven Rifle mod that affects Critical chance and Critical damage (positively or negatively) will shift between Point Strike's image and Vital Sense's image.
 * Interestingly, Riven Mods that affect Status Chance use Thunderclap's image as opposed to Rifle Aptitude's.
 * Riven is the past participle of the Middle English verb Rive, which means "to violently tear apart".
 * Taking into account the existence of 24 possible positive effects and the possibility of one negative effect, and the fact that effects don't fall into the same category, there are 12696 different Riven Mods with two positive effects and one or none negative effects, 267168 different Riven Mods with three positive effects and one or none negative effects, making a total of 279864 different combinations for a single weapon.

Links

 * Official Exhibit
 * Google Doc with possible stats in progress
 * List of All weapons Riven Dispositions
 * Google Doc for Riven Mod evaluation

Patch History
Mod Riven