This dlc adds Survival mode (An endless roguelike), New bosses and their respective weapons/mods on kill, and finally armor skins.

Survival mode is great to try out builds, weapons and it's genuinely fun, but it is also the main way to farm for Glowing Shards which are used to buy armor skins. You need a total of 550 shards to buy them all and you get like 10 per boss. You need to buy them if you want to get all the achievements so be prepared to listen to podcasts or watch video essays on the background because you're gonna spend a lot of time in this one. If you need some help, my favorite build is mod generation summoner.

The new bosses, mods and weapons and incredibly good and unique to the point they make the base game stuff feel boring in comparison.

The expanded Corsus Adventure mode is honestly really great, as it was an area that was quite lacking in the base game.

Overall a recommended dlc but dear god the grind for all the armor skins is quite a lot

I really hated this expansion at first due to the survival mode. It's really hard and found it frustrating. I'm a trophy hunter though so a friend and I kept trying to the point we were addicted once we learned the best equipment, combos etc. It forced us to try weapons and items we never bothered before finding some of them amazing. By the time we stopped playing we could make runs to level 15 - 17 without issue.

It's a hard one to recommend though as I can see how people could bounce off it but we had a great time with it after a rough start.