False Idols is a side mission in Far Cry 5. It takes place in Faith Seed's region of the Henbane River. This quest requires the player to destroy 16 shrines in the region. Doing so will increase the player's Resistance Points. The quest is also needed to unlock the Troublemaker achievement. The player will automatically get the quest after destroying 3 shrines themselves. A map can be found here.
Destroy 16 Shrines. An armed helicopter is recomended but the targets can be tricky to spot, since the Bliss gas surounding them blends with the terrain.
Destroy all the shrines in the Henbane River. This is easier done using a helicopter, but shooting them from the ground works too. Each shrine has an explosive Bliss container attached on its front side. Destroying the container will destroy the shrine.
$1600 and 200 Resistance Points.