Solo: To get to the pelican on your own, throw a plasma grenade on a shade
(Next to the door you enter the bridge from)and make the shade fly off the
edge of the bridge but try and get inside it as it falls down. You must try
and get the shade to hit the snow covered ledge on the way down otherwise
you will fall too fast and die.
To see the the generators from "Two Betrayals". Get a banshee by shooting
one down from the ledge where you see the first wraith tank. Once you have
one, pilot it back to where you shot it down and you'll see a locked door.
If you fly backwards into it and jump out at the right time you'll be able
to get through the door. This is real tough so keep trying. Once your in,
the texture mapping will be gone and everything will be real quite. You'll
be able to see a generator there but it won't be operating. You can find
another one at the end of the map also. Where the two banshees are on the
bridge. Theres another ledge to the left.
At the end of the map, take a ghost up the top of the pyramid shaped
structure and go the the large door. Don't open it, instead pilot the ghost
sideways level with the door, and if you jump out at the same time you'll
fly through the door. Inside, a group of enemies will be standing there
completely ignoring you even if you shoot them. You can kill them but they
don't react to anything, note that they are not frozen but normal breathing
covenant. If you open the door you got through the enemies will suddenly
turn and start attacking. You can do the same ghost trick to get through the
control room door and explore inside. To get back through a door, walk next
to it until you see the message to press "X". Press "X" and you'll get
inside the ghost on the other side of the door. Note if you use a banshee to
get through a locked door, you won't be able to get back out.
Co-op: At the beginning, both players get back inside the pelican. We
all know you will die on the way down, this is because the pelican scrapes
along a wall and you fall out just like the banshee. But if one player jumps
out and flips the pelican, it will change the direction the pelican is going
and you'll likely make it to the bottom of the area. The other player will
respawn at the bottom when you get out. It's very misty and you'll have
trouble looking around.
To get on the pelican you see on the first bridge, jump off the bridge and
land on the lower ledge (the damaged wall). Then try and get a player to
respawn on the ledge with covered in snow. If you managed to do that then
walk round to the pile of rocks and jump down to them. You'll slide down the
side of the rock and take no damage. Then run towards the pelican and press
"X" to enter. You'll go for a little ride then it'll land next to another
pelican. Now there will be no more enemies in the level.