Skulls are found in multiple places throughout the Banoi Island, and when placed where they belong, unlock developer crafts which are much better than regular crafts in Dead Island. Skulls do not carry over into a new game so the player will either have to place them before they leave the island or pick them up again later. They also carry over from single-player into co-op and vice versa, and even if another person picks them up the player can use them. It may also be possible that if the player joins a person that has a skull placed, they may not need to have the skull at all and can just grab the mod. This may be easier to achieve if the skull was placed in the same session.
Green Skull: Act I. The skull is on the bottom of the Resort Map, west of Bunker 06. The player should look for the second path to the City Tunnel Gas Station, on the shoreline near a capsized sailboat, then follow it and jump behind the bush up on to the rocks and walk up and to the left. There will be a metal chest and the skull with a flag and a green arrow.
Purple Skull: Sewers in Act II. It is located on the second level accessed by ladder in the dead end; to get to the ladder the Hero must go through the right door instead of the left door (the door that doesn't lead to next objective right after killing the first Floater). It takes a bit of trekking but once the player's in the room with the three radiation barrels knocked over with a ladder, they're in the right room. They might be able to see a faint glow from the candlesticks around the skull on the second floor in a corner from the first floor depending on where they're standing at in the room.
Blue Skull: Act II. During the quest "Uninvited Guests", there is a bathroom opposite the kitchen. The Blue Skull is in one of the corners in a glass case. The Hero must first smash the case in order to be able to retrieve the skull.
- Note: Skulls may only be placed at their assigned altars, but not during a joined game.
Orange Skull Altar: Act II. It's in the Sewers, at the top of one of the largest rooms in the sewer between the City Hall and Supermarket. There will be water and flood gates, and then a ladder that goes up to a small platform with a door. When the player climbs the ladder, the door will be on their right and directly in front of them will be a zombie sitting against the wall near a propane tank. The altar is inside the room on the left.
Green Skull Altar: Act II, in the Supermarket. This altar is in an area directly to the right upon entering main market. There are shelves full of teddy bears, and one of these shelves is the altar.
Purple Skull Altar Act II, during the quest Uninvited Guests. One of the burners is lit in the kitchen — this is the altar. (Note: once the quest is completed, the Purple Altar becomes locked off.)
Blue Skull Altar: Act I. Bunker 06 in the Resort area will be surrounded by zombies, with a single survivor, Jose Garcia, to rescue. Once he is rescued, the player should travel through the manhole in the bunker to the other area of it. There is a metal door on the level, and propane tanks on the level above. The player must place the tank next to the door and shoot it to blow it open. The altar is on the wall underneath the big blue arrow.
Brown Skull Altar: The place is shown on the picture. The easiest way to reach the location is to go into the bungalow district near the altar. At the back of the a bungalow near the powerhouse at the golden bungalow district is a cliff drop that heads towards the marked spot. When the player reaches the tree, they should carefully move around the bushes and onto the rocks and then follow the rocks until they start to see greenery. The altar is tucked away in an indent there.
- Note: Names are lowercase in-game. All recipes require $10000 and 5 Diamonds. The weapons are all created by the recipe, so there are no need to craft them.
Green Skull: Developer's No. 2 craft "cr33zz revenge for endless crunch". (Parts needed: Battery.)
Purple Skull: Developer's No. 4 craft "mindblower". (Parts needed: Battery.)
Brown Skull: Developer's 666 craft "beware the power of glova".
In this quest, the player needs to recover four Red Skulls for Mongina. The skulls can be found in the Ghost Village. This quest needs to be activated before the player meets up with Mowen, otherwise Mongina won't be able to talk to them.