Far Cry 5 - Side Effects solution

How to find and complete Far Cry 5's Side Effects treasure puzzle.

Guide by Dom Reseigh-Lincoln Contributor

Updated on April 10, 2018

Far Cry 5 Side Effects is a puzzle you have to solve within the Henbane River region.

It's one of many Prepper Stash locations you'll find throughout the game, all giving you rewards once you solve and figure out how to access them.

If you're interested in other Far Cry 5 guides, we have have articles on endings, fishing and perks.

Side Effects solution

Location: Bright Warden Radon Spa

Rewards: $1,000, 3 x perk magazines

Prepare for one of the most creepy and unsettling side-activities you'll take part in while playing Far Cry 5.

You're about to descend to a radon mine, so expect lots of hallucinations, voices in your head (from Faith, no less) and lots of things going off and exploding for no reason. There's also going to be quite a few Angels, so let that be a warning.

You can find the Bright Warden Radon Space southeast of Hope County Jail - you'll know you're in the right place because a truck full of loot will be parked near the bridge leading to the mine (defeat the heavies guarding it and there's a new 4x4 inside for your troubles).

Cross the small bridge and you'll see a hut and a door leading to the mine. Read the Prepper Stash clue on the boxes outside to start the mission.

Inside you'll see a locked door to your right - you'll now need to explore the mine and find the power switch to clear all the gas. Turn left, then right to encounter a wooden barrier. Destroy it, then head left and follow the tunnel.

Turn right and shoot out the barrier. You'll now reach a sea of green fog with some Angel bodies on the other side - this is actually a drop (it won't hurt you, but you'll need to climb up the other side). Head down the stairs, shoot out the doorway and kill the rattlesnake inside the door to your left.

Crawl underneath the rocks to your left, then use the shelving on the left of the small chasm to reach the other side. Climb up, to left then flip the switch to turn the power back on and vent out all the gas.

Now it's time to head back the way you came. There will be around five or six Angels now patrolling the route so take them out or simply run past. The door at the start will now be unlocked - head inside to grab your Prepper Stash bounty.

Looking for more Far Cry 5 guides? Learn how to complete the Arcade Dawn Live Event this week, and when you're back in the campaign, make use of our Prepper Stash locations list, which are among the most interesting missions in the game. As well as Far Cry 5 animal locations, we have an in-depth look at how to fish and hard fishing spots, as well as Bass, Trout, Salmon and Sturgeon locations. All of these can help you unlock Perks in the Challenges List, and ultimately, unlock those Far Cry 5 endings.

While you're here, check out other Prepper Stash locations within Henbane River (Faith's region):

Each one will have a different collection of items, ranging from ammunition, to perk points to weapons and they're an ideal for players in their early hours of play to bank plenty of cash and unlock those perks.