Golden Skulls
Iron: 1P death restarts game, Co-op death goes back to last checkpoint.
Black Eye: After Taking damage you have to melee it back but energy sword and grav hammer work too.
Catch: Enemys throw grenades thrice as much.
Tough Luck: Enemys dive out from grenades, vehicles, and melees.
Overcast: Radar turned off.
Famine: half as much ammo as before.
Thunderstorm: All enemys upgraded to a higher rank.
Foreign: Cannot use enemy weapons or vehicles.
Tilt: Enemys have 150% damage
Mythic: All enemys have stronger health
Shield: All enemys have sheilds
Silver Skulls:
Blind: Everything in the HUD is gone enjoy the view
Sputnik: Melees and Explosives have a 3x as much power
GBP: Confetti!
IWHBYD: Rarer dialogue and vice versa.
Bandanna: Bottomless clip.