Releasing earlier this year to rave reviews and widespread audience acclaim, Doom Eternal is easily already one of the biggest games of 2020, following up its now-revered 2016 predecessor in style. It's even got a new DLC releasing soon, with players jumping into a series of new missions when The Ancient Gods releases on October 20.

Until then, however, it seems Doom Eternal players on PC will be getting a new slice of unofficial content when renown Doom modder Proteh's Horde Mode releases on September 13. On top of announcing the highly-anticipated mod's release date, Proteh has also dropped a short launch trailer which shows off a little more of how the game mode works.

RELATED: Doom Eternal: Ancient Gods DLC Has 'A Lot' of the Game's Toughest Enemy Type

Clocking in at just over a minute, the footage begins with the notorious monologue from Eternal's trailers, prepping the Doomslayer for action. Cut to reams of gory Doom action, with the Slayer navigating around an enclosed arena as he rips and tears his way through an endless barrage of both early and late-game enemies. It seems pretty apparent that things only get more challenging as the waves press on, with the video showing increasingly crazy numbers of enemies. The promo caps off with the Doom Slayer wielding the Crucible and facing down his demonic offence, as a hellish voice tells him "we're not done yet" and the words "final round" echo throughout the arena.

Proteh has promised that Horde Mode will offer a hardcore Doom Eternal experience that will challenge even the game's most hardened veterans, so expect the mod to be a great piece of endgame content for those who feel they've fully conquered the main campaign. According to Proteh, Slayers enter the arena with only the base shotgun and amass a full loadout as they press through the waves. Finishing a wave awards ammo, lives, weapon mods, sentinel crystals, and more, with the catch being that each round ramps up the difficulty. Along the way, Slayers will have to take part in gruelling boss fights (which feature buffed up enemies) and attempt to progress to the endless final round, which is allegedly ruthlessly difficult and tasks players with surviving as long as possible.

It sounds like an amazing new experience for fans of Doom Eternal, many of which are looking for new ways to test their skills while they wait for the release of The Ancient Gods. The upcoming DLC will seemingly be worth the wait, however, with ID Software claiming it's expansive enough to be a whole new game in its own right. It actually technically is, with the team announcing that it'll be a standalone expansion that's playable without owning Doom Eternal itself.

Doom Eternal is out now on PC, PlayStation 4, Xbox One, and Google Stadia, with Nintendo Switch, PlayStation 5, and Xbox Series X versions on the way.

MORE: Doom Eternal and The Elder Scrolls Online Coming to PS5, Xbox Series X