The Risk of Rain 2 Alloyed Collective expansion added more than just one final boss. Apart from the big robot ball inside Solutional Haunt, players also get to fight a secret boss later on, but only if they use the correct items in the correct places. The true big boss of the DLC is hidden further inside the Collective’s realm, and it is easily the best and most challenging fight in the game thus far. If you want to experience the new endings (& unlock more stuff) for Risk of Rain 2, here’s what you need to do to fight the true final boss of the Alloyed Collective DLC.
Risk of Rain 2: Achievement/Trophy Guide
Getting every trophy/achievement in Risk of Rain 2 can take a while due to range-dependent factors.
How to Fight the True Final Boss of Risk of Rain 2 Alloyed Collective
First, you’ll need to make your way to Solutional Haunt and beat Solus Wing, which is easier said than done. Solus Wing is definitely one of the harder bosses to fight in the game, and if you’re using a melee character like Mercenary, you’re probably going to have a lot of trouble just trying to beat Solus Wing.
As a refresher, you need to find and activate an Access Node in the third world of your playthrough to reach Solus Wing, and if you haven’t unlocked Drifter yet, make sure to take some time getting her out of her prison too. When you get to Conduit Canyon, keep at least one extra Sentry Key for later.
Once you beat Solus Wing, you’ll get an item called the Encrypted Cerebellum. Make sure to pick that up, then head through the portal in Solus Wings’ eye. You’ll arrive at a bazaar of sorts, and along the left end of this bazaar, you’ll find CHEF manning a kitchenette. Interact with CHEF, and he’ll let combine items for you. Give him the Encrypted Cerebellum and any of these other items:
- Sentry Key
- Prison Matrix
- Empathy Cores
- Encrusted Key
CHEF will combine the two items and give you an Exposed Cerebellum. Take that item and give it to the big Solus unit near CHEF’s kitchenette. The Solus unit will open a Decrypted Portal, which will lead to the boss fight versus Solus Heart.
Solus Heart is a very dangerous enemy, and he can easily delete your entire health bar if you get by some of his attacks. If you’ve properly built your character, you should have a better chance at beating him. Once you do defeat Solus Heart, you can either accept his offer or reject it. Either way, you’ll unlock a new skin for your character (but only for the base game survivors).

