Capturing Mandalf may make him permanently occupy space in the Prison

Can't confirm internally.
Please upload output_log and savefile

It's tricky to reproduce. The first time I found it out was when the level glitched. Instead of a few seconds to disappear and then reappear at the Gateway, Mandalf took much more, allowing me to capture him w/o doing anything out of ordinary. So now I had to kill and imprison him as fast as possible. Here is the savegame where all conditions are met to reproduce: Savegame.7z.

• Build a Prison for two units somewhere close to the Mandalf's Archive. It should be used for the Templars there.
• Breach into the Archive.
• Use a Sentinel to occupy the enemy attention while a Worker is claiming the room.
• Sell the Archive and build a Prison here. You may need to move the Sentinel away while you are doing so, otherwise it may kill Mandalf too early.
• Kill Mandalf and imprison him quickly.
• Wait for him to disappear. Check the Prison. It should say it contains 1/1 prisoners.

So I gave this a try last week. Unfortunately I wasn't able to get it right at the cusp of the first Mandalf spawn as ZzZombo has.

I tried with the Second and Third Mandalf spawns but the problem didn't seem to occur with them, so I have a sneaking suspicion this is only an issue that occurs on the first spawn. I'm going to pass this on to Code to see if there's any circumstance where this could occur with the first Mandalf Spawn.

Did you use my savegame though? If you do, you'll only need to do last few steps.