All player units have 50% more hitpoints.
Destroy 100 Sentinels
To reach 100 Sentinels, construct as many turrets and Hornets as possible. Constantly check the sides of the ship, as the robots tend to congregate there. The skull will pop into existence at the front of the Spirit of Fire, floating in the air below the observation deck. You'll need a flying unit to get it.
Black Box #11: You'll need a Hornet for this one, too. It's resting on the northwestern flank of the ship, at the opposite end you found the skull. Note that by "flank," we mean the very edges of the Spirit of Fire... beyond the fences, where the ship slopes downward.
Skull #12: Boomstick
Description: 5% chance any non-player unit blows up upon death with explosive area of effect damage.
Requirement: Kill 12 Spirit Transports
Same strategy as the last mission. Build as many turrets and air units as possible to destroy the transports before they fly away. Also try upgrading your Marines to have the RPG ability. The skull materializes on the northeastern tip of the ship, right above the text reading "Spirit of Fire" and "Captain Cutter". You'll need an air unit to reach it.
Black Box #12: Like the last crate, this is on the outer edge of the ship (northern flank, southern tip), but tucked closer to the outer fences. Again, you'll need an air unit.
Skull #13: Pain Train
Description: All player units train 50% faster.
Requirement: Kill 10 Bomber Forms
Check dark corners of the map for Flood infestation and the bulbous blimps you need to annihilate. When you've killed ten, the skull will be waiting for you in the Flood-filled valley north of the mission's first teleporter.
Black Box #13: Head to the northeast edge of the map. Go to the middle of that edge. On a very high and flower-covered cliff is the crate. Pretty, ain't it? You can reach this vista with a ground unit, but as usual, an air unit's a lot easier and quicker.
Skull #14: Bountiful Harvest
Description: Supplies come in 25% faster.
Requirement: Kill 20 Vampires
You'll destroy twenty Vampires just trying to stay alive in this mission. The skull appears at the top of the third ramp, behind the second Covenant base, and is surrounded by a half circle of purple crates.
Black Box #14: This crate is hidden southwest of the first Covenant base and the possible location of your second UNSC base. It's in a raised grass rectangle, bordered by metal, and you'll need an air unit to get there.
Skull #15: Emperor
Description: All player powers recharge in half the time.
Requirement: Kill 3 Scarabs
Possibly the trickiest skull to collect. The Scarabs tend to wander around the center of the blue ring, but they're difficult to destroy and the mission is timed. We recommend building a Field Armory and researching enhanced versions of the MAC Cannon. That way, you can destroy each Scarab with three or four instantaneous blasts from the sky. The skull is in the northern (slightly northeastern) area of the map, amidst a large infestation of Flood.
Black Box #15: Compared to the skull, this is a piece of cake. Just take a Warthog from your original base, drive north across the blue ring structure and you'll see the crate in a very obvious location.
Mar 6, 2009
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