Half-Life: Source

You can finally rescue Half-Life's guards and scientists thanks to this mod inspired by Lemmings

A new mod for Half-Life: Source, inspired by Lemmings, allows players to rescue scientists and guards who were previously unrescuable in the original game. The mod enhances NPC navigation and combat capabilities, covering approximately half of the game's content from the 'Unforeseen Consequences' chapter up to 'Apprehension'.