Following it’s release it March, Doom Eternal’s first DLC has now gone live and is available on the Stadia store now as an Add-On to the Doom Eternal or as a standalone title.
You do also have the alternative of the Year One pass that is also available now.
“The Ancient Gods – Part One is the first campaign expansion for the critically acclaimed DOOM Eternal. Your war is not over… slaying the Khan Maykr left an imbalance of power that threatens all of creation. The legions of Hell have razed the heavens, threatening to expand their control across dimensions. With the aid of an old ally, battle your way back to Urdak and decide the fate of the cosmos.
Your mission is now your own.”