Finding skulls has always been fun, but it is kind of a double edged sword. Finding one is fun but using it usually is not. In this vein, I suggest including skulls with positive effects in Halo: Reach. The effects could range from temporary arbiter like invisibility to total invincibilty. Of course, to balance this, normal achievments would be blocked when using these skulls. Instead, there would be certain achievements which you could do using the skulls in certain combinations. For example, clearing an entire level without a single enemy spotting you (invisibility skull) or doing an entire level with one continuous kill spree (invincibility and infinite ammo, maybe increased movement speed). So my question is; would you like to see these skulls in Halo: Reach? Why or why not?
Skull Ideas:
Invisibility, Invincibility, infinite ammo, low gravity, explosive rounds, rapid fire (speeds up single shot weapons like snipers and rockets).
Achievement ideas:
Sneak through an entire map, get a continuous killing spree, don't get hit once.