ent_fire
ent_fire is a console command available in all 
Source games.
It is a debugging tool to fire inputs on entities. It's an essential tool for both programmers and mapmakers, allowing them to easily debug problems in a map's entity logic.
Different entities can handle different inputs. Entities will ignore inputs that they don't know how to handle. To find out what inputs an entity handles it is most reliable to type ent_info <classname> in the console, which gives you a list of all the inputs (and outputs) known to the entity it found matching the <classname>.
Usage
ent_fire <classname_or_targetname_or_wildcard> <input_name> <optional_parameter> <optional_delay>
This would fire the specified input on all entities with a matching classname or targetname. The input will contain the overriden parameter if it was specified. The input will be fired immediately, unless the delay was specified, in which case it is sent after that number of seconds.
Tip:The game will auto-complete both existing targetnames or inputs when typing ent_fire or ent_fire <targetname> followed by a space in the console, respectively.
Bug:The delay parameter only accepts whole numbers. Anything past a decimal point will be ignored. [todo tested in ?]Examples
ent_fire relay_start_assault Trigger
- This would find all entities with classnames or targetnames of "relay_start_assault", and call their "Trigger" input. Assuming that "relay_start_assault" is a logic_relay, this would cause it to trigger and fire all its outputs. Very useful for debugging a part of a large chunk of entity logic in a map.
ent_fire bob_the_soldier SetHealth 5
- This would find all entities with classnames or targetnames of "bob_the_soldier", and call their "SetHealth" input, with a parameter of "5". Basically, the NPC named "bob_the_soldier" would have his health set to 5.
ent_fire !picker Kill
- This would find the entity currently under the crosshair, and call the "Kill" input. The "!picker" targetname is a special targetname that finds the entity under the crosshair. The "Kill" input is known to all entities, and basically tells the entity to immediately remove itself. An alternative to this is the impulse 203 command.
Warning:NEVER use the killinput on!player– the player entities or worldspawn, this will crash the game!
ent_fire counter_combat_* Add 1
- This would find all entities with classname or targetname matching the wildcard "counter_combat_*", and fire their "Add" input with a parameter of "1". Assuming all the entities found are math_counters, this will add 1 to their current counter values.
ent_fire npc_barney Ignite
- This would find all entities with a matching classname or targetname and ignite them.
ent_fire player Ignite
- In a multiplayer game with cheats on, lights all players on fire.
ent_fire player IgniteLifeTime 5
- In a multiplayer game with cheats on, lights all players on fire for a time, in seconds. This will light all players on fire for 5 seconds.
ent_fire player ModelIndex <integer>
- In a multiplayer game with cheats on, will change all players' player models to a precached model.
- Warning:NEVER use the ModelIndex input to change a player to a model that is invalid in the map's model precache. This will crash all connected players.