DOOM 3

Base (based on original release)

 * admin - Only invoked by GUI panel
 * alphalabs1 - Only invoked by GUI panel (elevator group)
 * alphalabs2 - Only invoked by GUI panel
 * alphalabs3 - Only invoked by GUI panel
 * alphalabs4 - Only invoked by GUI panel
 * caverns1 - Only invoked by GUI panel
 * caverns2 - Only invoked by GUI panel
 * comm1 - Invoked by trigger_relay which in turn is only invoked by GUI panel
 * commoutside - Invoked by trigger_relay (linked to GUI panel) and GUI panel
 * cpu - Invoked by a chain of trigger_relays (started only by GUI panel)
 * cpuboss - Invoked by elevator group
 * delta1 - Invoked by elevator group
 * delta2a - Invoked by utter mess (but hey, you can hit a trigger)
 * delta2b - Invoked by elevator group
 * delta3 - Invoked by GUI panel
 * delta4 - Invoked by a touch trigger in isolated place of a map, which is surrounded by black texture (player gets telported there)
 * delta5 - Invoked by GUI panel
 * enpro - Invoked by GUI panel
 * hell1 - Invoked by a trigger_relay, which seems that have a bunch of requirements.
 * hellhole - No endLevel trigger. Ending cutscene triggered by
 * mars_city1 - Invoked by a trigger relay, started by elevator group.
 * mars_city2 - Invoked by elevator group
 * mc_underground - Invoked by trigger relay, which in turn is linked to hidden elevator?, speaker entity and 2 elevator brushes. All requiring after invasion trigger relay to be triggered (as it seems).
 * monorail - Invoked by GUI panel
 * recycling1 - Invoked only by GUI panel
 * recycling2 - Invoked only by GUI panel
 * site3 - Only invoked by GUI panel

Lost Mission (BFG)

 * le_enpro1 - Invoked only by GUI panel
 * le_enpro2 - Invoked by trigger relay, which in turn is invoked by trigger relay, which in turn is invoked by elevator group (also linked to a random speaker in the middle of a level, because LUL)
 * le_exis1 - Invoked by a trigger inside of an elevator shaft.
 * le_exis2 - Invoked by trigger relay, which handles teleportation to hell event.
 * le_hell - Utter mess, activated by touch trigger
 * le_hellpost ?
 * le_underground - Invoked by a GUI panel
 * le_underground2 - Invoked by a GUI panel (and tied to elevator door brushes as well)