They are skulls. idiot.
if you want to know where the skulls are all you have to do is go to youtube and put in "halo 3 odst mythic skulls" and it will show you how to get to them
There are 13 campaign skulls ( 9 gold ones which unlock achievements and 4 silver ones which make the game more fun ) and 6 mythic skulls ( 3 for the halo 3 mythic pack and 3 more for the halo 3 odst mythic pack )
yes u do
IT gives you gamer score points and you get them in forge mode
no.
Thirteen, Fourteen if you count the hidden skull on cortana. thunderstorm cowbell fog iron grunt birthday party blind IWHBYD (i would have been you daddy) tilt catch tough luck black eye mythic famine
archon armor
You get 1 of the 7 vidmaster achievements. Get all seven and you can claim the recon armor.
no. there is only human skulls on the campaign levels but there might be some on the mythic map packs.
It gives 255 gamerscore and 16 achievments
There are many skulls located throughout the campaign in Halo 3, as well as on the Mythic Multiplayer maps. Walkthroughs for individual skulls can be found on many websites, including Halopedia.