The Catch skull is one of the more difficult modifiers to deal with. This skull makes it so enemies throw more grenades. You will be dodging grenades left and right with it active. This skull is hidden in the far northern section of the map. Here is where you can find the Catch skull in Halo Infinite.
The Catch skull is in the northernmost section of the map. You can easily reach this area by traveling to Outpost Tremonious. Climb the cliffs behind the outpost and make the jump from there up to the northern section. Check the map above for reference if needed.
When you reach the area, you will be hunting for a small lake. This location is guarded by two heavily-armored hunters, so be careful. These hunters also have backup. A few snipers are in the area as well. We suggest taking them out before dealing with the hunters to make life a little easier. After taking out all the enemies, you can find the skull in a tree trunk that is filled with soldier helmets.