Help needed regarding custom units/structures

[Sobis]

Hello, I hope this is the correct place to ask for support. I am confused as to what 2 structures met in custom maps do:

Impeller. I've seen this structure in several maps but I have never understood what does it do apart from spinning when touched with a liquid. I've tried searching the forums, found a few results discussing it but I still couldn't figure out what it does. Example map: "At the end creeper win round 3" (No. 532)

V-Reactor; V-Storage. I'm not sure how common these are, it can be found in this map: "At the end creeper win round 8" (No 1110). I am yet to see this used in another map (though I don't play THAT much).

Can anyone please help with these?

[Karsten75]

I can help you with the Impeller, since I wrote the first incarnation of it and actually put some doc in the wiki (unfortunately the links from the game to the wiki came after I wrote it, so older maps don't automatically provide the link and one has to manually go to the wiki to look for it.

Impeller

The other unit, perhaps someone else can help you with.