The Swarm of Flies incantation is one of the few incantations you can find in the Lands Between that causes blood loss when it hits a foe. This incantation is extremely useful for bleed builds and deals a lot of damage if used correctly. Of course, a spell like this isn’t easy to get. Here is where you can find the Swarm of Flies incantation in Elden Ring.
The incantation is waiting for you in Mohgwyn Palace. Obviously, you need to reach Mohgwyn Palace first. This can be done in two ways. First, you need to follow Varre’s questline. This will lead you to ultimately get an item that teleports you to Mohgwyn Palace. This can also be done early on in the game if you are looking to get the incantation as soon as possible. You can also reach Mohgwyn Palace by using the portal to the northwest of the Yelough Anix Ruins near the Runebear. The second method takes longer because you need to reach the Consecrated Snowfield to find the portal which can’t be done until you have defeated Morgott in the capital city.
Once you reach Mohgwyn Palace, head north into the large area filled with blood and red Albinaurics. Be careful, the Albinaurics can grow spikes and roll pretty quickly toward you, causing blood loss. Follow the cliffs on the right side and you will find a cave. Keep following the cliff face until you reach the second cave that has two Ablinaurics in it. The incantation will be in the back of the cave.