You can't become "skull level".
There are two types of "skull levels". When a player's level appears to you as a skull, it means he is more than 10 levels higher than you. If he is 11 levels higher, and you gain 1 level, he will no longer show a skull - you'll see his actual level.
Raid boss levels are depicted as a skull as well. This simply means that they act as if they are 3 levels higher than the maximum level that a player can attain. There's nothing you can do about that. They are designed to require good gear (and 10/25 players) to defeat.
level 8 vampire,skull,bat,vampire,skull in level 9 vampire,skull,bat,vampire,skull
Level 2: Bat-Vampire-Bear-Skull Level 3: Bat-Bear-Bear-Bat-Bat Level 4: Skull-Bear-Bat-Bear-Vampire Level 5: Bear-Bear-Skull-Skull-Skull Level 6: Bat-Vampire-Vampire-Skull-Bear Level 7: Vampire-Skull-Bat-Vampire-Skull
Level 2: Bat-Vampire-Bear-Skull Level 3: Bat-Bear-Bear-Bat-Bat Level 4: Skull-Bear-Bat-Bear-Vampire Level 5: Bear-Bear-Skull-Skull-Skull Level 6: Bat-Vampire-Vampire-Skull-Bear Level 7: Vampire-Skull-Bat-Vampire-Skull
Level 2 bat, vampire, teddy, teddy, skull Level 3 bat, teddy, teddy, bat, bat Level 4 skull, teddy, bat, teddy, vampire Level 5 teddy, teddy, skull, skull, skull Level 6 bat, vampire, vampire, skull, teddy Level 7 vampire, skull, bat, vampire, skull
level 2:bat,vampire,teddy,teddy,skull level 3:bat,teddy,teddy,bat,bat level 4:skull,teddy,bat,teddy,vampire level 5:teddy,teddy,skull,skull,skull level 6: bat,vampire,vampire,skull,teddy level 7: vampire,skull,bat,vampire,skull and that's it the end is SO funny lol but the last level is hard
I forgot but bear, bear, skull, skull, skull is level 5
The Ark
Squirtle learns skull bash at level 40.
level 2:bat,vampire,teddy,teddy,skulllevel 3:bat,teddy,teddy,bat,batlevel 4:skull,teddy,bat,teddy,vampirelevel 5:teddy,teddy,skull,skull,skulllevel 6: bat,vampire,vampire,skull,teddylevel 7: idklevel 8: vampire,skull,bat,vampire,skulland that's all i know
The game Skull Kid has only two levels. After the second level is completed, Skull Kid goes to the boss. This is a game for frustrated and bored office workers as Skull Kid kills his co-workers and then the boss.
lv37
vampire,skull,bat,vampire,skull