You can play on any difficulty you just have to find them
First off the difficulty has to be on normal or higher. Next if you are trying to get the first skull on storm then you can not destroy any of the wraiths or the skull will vanish but you can destroy the anti air.
Skull Island is the fictional Indian Ocean island that is the setting for "King Kong".
You have to play on at least normal.
Skulls modify certain aspects of the campaign, often increasing difficulty. For instance, the Blind skull completely eliminates your HUD and the Mythic skull increases your enemies' health. Some are amusing, such as Grunt Birthday Party, which causes confetti to launch into the air from a Grunt that receives a headshot.
Every Skull, except the Blind and Assassins Skulls, are only available on Legendary difficulty.source: http://halo.wikia.com/wiki/Halo_2_Skulls
If you don't start the level from the beginning the skull won't appear. If you did start from the beginning i don't know.
Please specify which GAME your playing.
No you cannot, you must start from the beginning of the level. It also must be on normal, heroic, or legendary difficulty, or the skull will not show up. Even if the skull may be at the end of the level, you must still start at the beginning If you are trying to complete the game on legendary, and you have passed the spot, I recommend beating it first, and then replaying it on normal difficulty. Good Luck.
you have to beat it on all difficulty levels and obtain every hidden skull in the game.
yes but you can only find the skull if you play the whole mission from alpha point
The part of the skeleton called the skull is the head.