Half-Life 2: Episode Two

Half-Life 2: Episode Two is the third part of the yet-unfinished adventure of Gordon Freeman where Eli Vance prepared for "Unforeseen Consequences".

Unused Models
m6mLEHENCVY Episode Two contains a few unused models, some of which are leftovers from the original game.

Source Particle Benchmark
This is a demo of the new engine improvements, like shadows and particle showers. But people who have dissected the files have found some early content related to Episode Two within. The file level_voices_episode_02.txt shows there were some differences in speeches and that there were two cut characters.

Combine Advisor Unused Particle Shield


Found as "advisor_psychic_shield", this unused shield uses the Particle system shown in the Benchmark, but the file is found in the retail version.

Unused Combine Advisor Battle AI
gL655A9EtxI This video shows unused Combine Advisor Battle AI, hinting that Gordon was originally to fight one in Episode Two. However, recreating this behavior means a rebuild of the game engine to get it to work.

Unused Citadel Explosion Animations
DAVNgpVLoqA There are various unused explosion animations for the Citadel that are never used in-game. It can be heard at the end of Episode One, but it can't be seen due to explosions surronding the whole screen and fades to white.

Jalopy
A vehicle seen in the gameplay demos, but didn't make it to the retail and was replaced by the Muscle Car in the retail. The vehicle bears resemblance to the Scout Car from the original game but it based off a Volkswagen Beetle but it was stripped down for the game. However, the texture and handling files (but can be usable in the game via modifying) remain in the retail folders. It worked the same as the rest of the cars in retail.
 * There are plenty of mods online to restore this car but replaces the current Muscle Car.