The Culture explores 40K II: Now With 100% more Fanfiction

[Brother Oni]

thus the 'relatively'. Non lethal in this case would be big spiky clubs that make shooting noises when you hit things with them. Then watch the Culture have a mental meltdown when the clubs somehow shoot someone.

And a bright flash. And an electric shock.

At the risk of cross-franchise contamination, have you guys really just come up with a viable excuse for the orks to have lightsabres?

The Third War for Armaggedon. Gahzgkull's Orks test their teleporter technology on... I think it's Piscina. Then they head to Armaggedon, and prove themselves capable of launching attacks on the surface from a base out in the halo regions of the system. I seem to recall them using this to take out some of the anti-orbital weapons their fleet might otherwise have to worry about.

Orkish accuracy being what it is, I'd be surprised if more than 1 in 100 of their strike teams ended up in the right place (or in one piece).
However if you throw enough orks through a teleporter, you're still going to end up with sufficient survivors to cause problems on the other side.