- Main article: Kuva (Variant)
Kuva weapons are a special variant of existing weapons carried by a player's Lich and can be acquired once the Lich is Vanquished. If the player has enough weapon slots, they can claim these weapons from their Foundry. The weapons vary in attributes, dependent on the Lich the player has slain. The Energy Color on the weapon is depicted by what elemental bonus was augmented on the weapon during Lich creation and the progenitor Warframe.
Prior to Hotfix 27.1.2, Kuva Liches were guaranteed to have a different weapon than its immediate predecessor, preventing players from generating Liches with two of the same weapon in a row.
Notably, certain Kuva weapons are not based on existing Grineer weapons, and exist solely in the Kuva variant:
A Kuva variant of a weapon will only provide mastery points once, a second weapon of the same variant but with a different Lich name will not provide extra mastery. These weapons have a max rank of 40. To obtain the maximum rank, the player must polarize the weapon five times, with each Forma increasing the maximum possible rank by 2 (similar to Paracesis). The weapon's base damage is based on the Kuva Lich's percentage of bonus damage.
All Kuva weapons deal innate elemental damage in addition to physical damage. The amount of this damage is random, ranging from 25-60% of the Kuva weapon's base damage, while the type of element is determined by the Progenitor Warframe, as per this table.
Players can upgrade and/or replace a Kuva weapon’s innate damage bonus with one from another Kuva weapon of the same type (i.e. Kuva Seer can only be fused with another Kuva Seer). This process destroys the donor weapon and overrides the host Kuva weapon's element while retaining any applied Formas, Orokin Catalyst, Focus Lens, Mod configurations, Appearance configuration, Lich name, etc.
For example, Kuva Seer A has 25% Cold bonus and a Catalyst installed, while Kuva Seer B has 43% Heat bonus. Fusing B to A will override the Cold from A with the Heat buff from B, while A will retain the installed Catalyst, and B will be destroyed. The % bonus will be the highest of the two weapons multiplied by 1.1 and rounded to the nearest whole number, which would make the final bonus 47% Heat.
Using donor weapons with high % bonus values tend to have greater yields than fusing with lower % bonus values. As such, it is advised to preserve donor weapons and fuse starting with the high % bonus values.
Valence Fusion can be accessed in the Action tab at the bottom of the Upgrade screen of the desired Kuva Weapon.
Kuva Liches have a 20% chance to be created with an Ephemera equipped that corresponds to the Progenitor Warframe that killed them. These Ephemeras can be equipped on Companions. If the Kuva Lich has an ephemera, the player will receive it regardless whether they choose to vanquish or convert them.