UNDECEMBER frames its dark fantasy setting around the arrival of Serpens, an unexpected being whose existence unsettles a world created by twelve divine figures. That myth gives context to an action RPG built around fighting through enemies and growing stronger by acquiring items, rather than following a narrowly prescribed character path.
Its defining choice is build-making without fixed classes. Characters can combine equipment and skills freely, with Strength, Dexterity, and Intelligence serving as build types rather than gear restrictions. Skill Runes provide abilities, while Link Runes modify their effects; both can be upgraded, making rune combinations a central part of shaping combat. The game’s examples include casting magic with a sword or summoning minions with a bow, illustrating how its systems invite unconventional loadouts.
The play format spans a main story, Chaos Dungeons unlocked after completing that scenario, cooperative Boss Raids for up to eight players, and free-for-all PvP. Guilds can gather up to fifty members.
