New equipment (known as 'Stigmata'), weapons, and Valkyries can obtained either through in-game crafting or through a gacha system. Valkyrie stats and skills can be customized with various weapons and equipment, which can be improved by using in-game resources. Each Valkyrie has unique attack, evasion, switch, and ultimate skills, as well as a rock-paper-scissors-based character type to fulfill different team roles. During battle, players may freely move their character around the battlefield and switch between their three deployed Valkyries to adapt to various enemy types. Honkai Impact 3rd has players control a team of up to three characters, known as ' Valkyries', in real-time combat against various enemies.

The game starts out in the post-3rd Impact era. Honkai Impacts, also referred to as Honkai Eruptions, are large-scale Honkai disasters that coincide with the birth of a Herrscher. The 'impact' part of the title is absent from both the Chinese and Japanese versions, but adds context. The word 'Honkai' is a corruption of the Japanese 崩壊 (ほうかい, 'collapse' or 'decay'), pronounced 'hōkai', which is the direct translation of the Chinese 崩坏 (bēng huài) used in the original Chinese title.

Conan exiles co op mode