The Hammerwatch franchise is interesting. Following the excellent Heroes of Hammerwatch roguelike, indie developer Crackshell released the super buggy Hammerwatch II and, to my knowledge, never fixed it up. Despite that misstep, Crackshell and Team17 then returned to the roguelike formula with Heroes of Hammerwatch II on Steam. This one is very good, and some of our team has spent dozens of hours on it so far. Well, the game recently gained even more replay value with the release of the "Celestial Ruins" DLC. It adds a new. a survival mission, unique equipment, and more.
Official description:
"Celestial Ruins" is the first Expansion to Heroes of Hammerwatch II, a rogue-lite action-RPG that offers extensive persistent progression.
Undertake a new mission to a holy sanctum that's fallen to corruption. Battle hordes of enemies to summon an all-new boss with five variants. Experience the holy power of the new Priest class.

Features:
- Play as the Priest, a new class focused on mana powers and regeneration.
- Tackle a survival mission set in the Celestial Ruins.
- Battle the five Spirit bosses, each tied to your chosen divine blessing.
- Acquire powerful Spirit Boons that open up new build opportunities.
- Kit out your characters with new equipment: sceptres, lanterns and a plethora of new trinkets.
- Bring the new Will O' The Wisp and Animated Candle pets along on your adventures.

While we haven't tried the "Celestial Ruins" expansion just yet, we do feel safe in recommending Heroes of Hammerwatch II. After a short single-player tutorial, players can host or join online co-op games for up to 4 players. Like the previous Heroes, the gameplay during runs is quite challenging. This time, reviving a fallen player adds a health penalty to both players, so things get harder the more that someone dies.
A single run can take 1-2 hours, but there are also single-use maps that allow for shorter sessions and high-level rewards. While a run ends when everyone dies or completes the run, there are plenty of permanent upgrades to buy in town, so raising up characters provides plenty of long-term play. We'll try this DLC soon and report back with more detailed impressions!
Heroes of Hammerwatch II sells for $19.99 on Steam. The Deluxe Edition, which bundles the game with the "Celestial Ruins" DLC, regularly costs $24.99 but is on sale for $12.49 through September 14. That's a good price for hours of co-op roguelike goodness! The DLC costs $6.99 by itself on Steam.