Starting a Mission (Apocalypse)
General suggestions and hints on how to start a mission.
For basic information of the playing field: Battlescape.
For in-depth information: Agent Attitude and Arming Your Squad.
To start a ground (battlescape) mission, an X-Com agent(s) must be at a building or be able to travel to a crashed UFO.
Preparation
Equip a squad (usually six to twelve troopers in total, or single agent if you prefer) with armor, weapons and grenades at minimum. Other devices to use would be suited to the task you want to perform.
The few requirement for particular goals:
Convince the aliens to come with you = bring stun grenades and stun grapples (other options to stun aliens may be available).
Kill the meat, save the metal = non explosive weaponry to limit destroying items dropped by the dead and damage to structures.
Kill em all, no mercy = launchers and ammuntion, many high explosives, incendiarys... and a bad attitude!
Stun raiding for fun and profit = weapons that stun only, don't even need armor.
An agent should not be heavily over encumbered, if at all. Suitable items for suitable troops. Rename your agents (click on their name) to indentify those with particular loadouts or skills etc. Humans are well rounded in combat, Androids are immune to mind games, Hybrids are your (future) psi-troops.
Transport
Travel to a building is possible via the people tube network (slowest), using a road vehicle (slow), or using airbourne vehicles (fastest). Travel to an alien crash site is only possible with air craft.
To place agents into vehicles, or to remove... READ the fine manual!
Agents moved to a building via the tube network, or by road vehicle, go to the Base Terminal (it looks like a carport and is the 'heart' of the building). The Base Terminal is vunerable to damage if the building collaspes.
Agents arriving at a building via airbourne craft land at the launch tube and stay there until take off. Launch Tubes which are at ground level are safe from collaspe and can only be destroyed by weaponry.
If an "Alien Detected" alert has appeared, selecting a vehicle with agents on-board and then clicking the Alien icon will send off immediately to that location.
Starting
When you have your troops at a building (irrelevant whichever transport method was chosen), click LMB on the building to display the squad present. Two of the four buttons on the top left determine what happens next: Search or Raid.
Alien craft which have been shot down can only be reached with air vehicles and only when they have impacted the ground ("UFO crash lands" message and the UFO is smoking). When your transport craft targets the crash site and 'lands on the UFO's roof', the UFO crash recovery mission will immediately commence.