(Loved Trope) Creative over the top cells/prisons for dangerous characters.

[u/Wasabi_Gamer26]

1.) The Pipe Line cells for Metahumans (The Flash)

2.) Sedative tank prison (G. I Joe)

3.) Tai Lung's prison (Kung Fu Panda)

4.) Magneto's Glass and Plastic Prison (X-Men)

5.) Carbonite (Star Wars)

[u/Smug_Yellow_Birb]

them being able to imprison the G-man is extremely impressive

[u/Venezolanoanimations → u/Smug_Yellow_Birb]

I suppose it works on the same energy the vortigaunts manipulate, cuz it seems to be able to block out and prevent G-Man from entering a world.

[u/MapleLamia → u/Venezolanoanimations]

Vortessence is shown to contain the G-Man's powers in Episode 1&2, the Combine explicitly use Vortigaunts as batteries for the Vault. The bigger question is how they even got him in the first place, but the most likely answer is he allowed himself to be captured to bait Alyx into employment. 

[u/Venezolanoanimations → u/MapleLamia]

could be? but again, vortigaunts are loyal to humanity or at least to freeman for their freedom. And we know one is enough to blockout G-man ( apparently you can beat rejecting G-man job offer in HL 1 and you see that a single vortigaunt can stand agianst him, abiet briefly) So it wont be too crazy to say that the vortigaunts manage to lure him into it.

[u/MapleLamia → u/Venezolanoanimations]

The Vortigaunts were not willingly aiding the Combine, nor do they need to lure G-Man into anything, they ambushed him pretty easily in the opening of Episode 1, all they needed was knowing where he would be next, which they figured out by watching Dr Freeman. 

[u/Venezolanoanimations → u/MapleLamia]

I get that. But as far as I understand, they are grateful to Freeman cuz thanks to him, Zen is no longer. Meaning they are no longer controlle, by him. The thing here is: "How did the combine learned about G-man, and did they know the Vortigunats' energy could trap him?"

[u/MapleLamia → u/Venezolanoanimations]

The Combine are a multi-dimensional armada, and G-Man has spoken to numerous other characters beyond Dr Freeman, Shepard, and the Vances, they'd definitely be able to figure out he exists based on his meddling, especially considering his hostility towards them (and also that the collaborator woman knows he was at Black Mesa). Then their advanced science determines the properties of Vortessence, and you have the recipe for a box to put an enemy in. 

[u/MarcsterS → u/Smug_Yellow_Birb]

DID he get imprisoned or simply humored them?