The Deja-vu one is a little harder I feel but essentially think rocket race with 4 people working together. The worst part is needing to kill every enemy before a checkpoint area to get the checkpoint. thats annoying and I'll say now, going in to this we will end up seeing that damn checkpoint often if we smurf up (mongooses aren't very ressistant and even a indirect hit will generally kill one of the two odst's on it, we regulary saw gunners get hit in the face by fuel rod rounds what had missed the mongoose entirely, driver lived mongoose survived but the party went back to the checkpoint because 1 person died) which is a guaranteed certainty, especially considering theres tanks, banshees and ghosts alongside the normal contingent of ground troops and drones to fight your way through, (good tactic is for one pair on a goose to speed straight down to the far end and begin clearing on foot back towards the other pair, this way they're in position to help secure the end zone for Dare and Vrgl especially since the elephant's shielding will begin to fail once they're at the end zone not before in most cases) rocket launcher with 999 rounds and smg is the way to go imho at least then for drones you can all hop off and shoot them down with the smg.

As for Annual, it doesn't seem too extensively difficult it's just going to be a little time consuming, the worst part of the level will undoubtedbly be the start fights against the flood because if one person ends up cornered and dying we'll need to do it all over again the floor tiles will probably just prove annoying to avoid but I've seen videos what consistently show the correct path to take but I figure we can figure this out mostly.

I acquired the Vidmaster Classic achievement yesterday I saw an ok video for it which helped. The guy frankly sucked at it but rather than follow the rooster teeth guide which uses the hog for the first sprint past the tanks he gets a ghost early by using the technique (don't bother playing patsy with the ghost, when it comes close and you have the jack ability, jack it and be done with that) in the first bit of this video. If you wanna know why I said he sucked, watch the video all the way through he dies like 10 times during this video alone.

Oh and fun fact about Endure...

Endure originally was designed to be done on legendary and to survive past the 7th set however they determined it was nigh on impossible and therefore toned it down to 4 sets and heroic.

For those with no experience of firefight and just how hard that would be, 7 sets on easy is difficult enough to live on and generally by the time the players have done 8 sets on easy they'll be wiped out completely because when you die and respawn nothing you have initially can even truly hurt anything except grunts with a headshot. 7 sets on legendary, is just impossible to imagine really, you're talking 4+ hours of fighting far tougher than anything thrown at you in the campaign mode in fact this would be tougher than trying the Halo 3 level Cortana with all skulls on. Considering by the time you get up to the higher set levels all skulls are on constantly (excluding iron because thats not ever on in firefight with the exception of the bonus rounds) and a wave of brutes can consist of 20 - 30 of the buggers you can understand that double health, promoted to the next rank brutes = more chieftans, more captains and more power armour give them an overshield too and you realize very quickly that it's not even close to a fair fight. On legendary the thought of it makes me shudder.