Call of Duty 4:
This is the only mission in CoD4, but it definitely deserves a spot on the top list. It's fast paced and one of the most difficult things to accomplish in any Call of Duty game ever on Veteran. It set a great precedent for future missions.
"We're going deep, and we're going hard."
"Surely you can't be serious."
"I'm serious. And don't call me Shirley."
Modern Warfare 2:
In the CoD4 campaign you experience the AC130's support briefly at the end of Hunted, and then you man the craft in Death From Above. The MW2 mission Overwatch recreates both of those even better by putting two players together and forcing both to communicate effectively their respective view of the situation and how to best deal with it.
Exceptionally difficult on veteran because of the timer and limited equipment, this one took me dozens of run throughs to finally beat with a partner, but was incredibly satisfying once it was done. Breaching is always fun and the pace once you get inside is tremendous.
Similar to O Cristo Redentor in its simplicity, except with a very large map, and more difficult enemies that have all already spawned on the map (except the juggernauts). Defensive play is rewarded in a way that I imagine is true to life, and clearing the house then defending it is pretty cool. I also enjoyed the map itself, a lush mountainous area in western Asia.
Modern Warfare 3
Part of the appeal of Milehigh Jack is that it brings back the feeling of Mile High Club, and the other part is that it complements the campaign mission Turbulence by showing it from the enemy's perspective.
I contemplated wether to include Smack Town or Hit and Run since they both take place on the same map which I consider to be one of the most interesting. The rusted ship remains, the docks, it's just a cool environment. But Smack Town has a bit more variety to the gameplay with the first portion being on the helicopter so I think it gets the nod.
Starting off as a captive and rushing through each stage to save the other hostages is very engaging. Completing it solo on Veteran is very doable, but it does take some concentration to save the hostages in a timely manner which makes it rewarding. Also playing co-op and seeing your executioner murder other hostages while moving toward you is exciting.
This mission is one of three that are maps that were not part of the campaign, Arctic Recon and Special Delivery being the other two. It's not a difficult mission even on veteran but something about the variety appeals to me more than the average mission. There's sniping, sneaking around at night, an EMP, a great looking fiery bridge, and the reaper gameplay mechanic is very satisfying.
In CoD4 there are 20 achievement points you can earn in Mile High Club.
In MW2 there are 340 achievement points you can earn only in the Spec Ops missions.
In MW3 there are 720 achievement points you can earn only in the Spec Ops missions (110 in the standard missions and 610 in the DLC missions).