Why wont it let me get the Orpheus achievement in halo 3?

[Purkey]

ive tried to get this multiple times but it wont give me the achievement when all my friends get it? what the heck? is it a glitch? please help.

 

[fornotbobhi]

this challenge is best done twice and in the right game mode or else it will not count and it will not give it to you The best way is to be the one who kills the oracle make sure you have the scoring on and you start form the start of mission and have the skulls turned on

 

[fornotbobhi]

this challenge is best done twice and in the right game mode or else it will not count and it will not give it to you The best way is to be the one who kills the oracle make sure you have the scoring on and you start form the start of mission and have the skulls turned on

 

[fornotbobhi]

this challenge is best done twice and in the right game mode or else it will not count and it will not give it to you The best way is to be the one who kills the oracle make sure you have the scoring on and you start form the start of mission and have the skulls turned on

 

[dumber_dan]

Try this:

-Play the game solo
-Start from the very begginning of the level, nothing in between.
-Note you cannot reload a campaign scoring mission if you quit out and want to go back to where you left off.
-Make sure you're actually getting to required point value. Sometimes you may need to get a few thousand more points instead of the regular 15,000.
-Silver skulls DON'T count as multipliers.