G: Mnemonica allows you to transfer lieutenant skill to someone with a cube, or G: Autotool. Unidrons have autotool, but are remotes and so cannot (according to text on loss of lieutenant page) be the lieutenant. Is the wording at the end of autotool supposed to overcome the ‘remotes can never be lieutenant’ issue, or is it merely wording for when (if?) we get another autotool unit? “Despite its lack of Cube, a trooper with the G: Autotool Special Skill may receive a G: Mnemonicatrooper's WIP value, G: Mnemonica Special Skill and Lieutenant Special Skill (if applicable)” The “important” box from ‘loss of lieutenant’ - “Troops with the Irregular Characteristic or the REM Troop Type on their Troop Profile cannot be appointed as Lieutenant.” ED
Autotool specifically allows models which couldn't be the Lt to be the Lt. Also you specifically don't go into loss of Lt because of Mnemonica.
Please note that you can't appoint an Autotool to become your Lieutenant. It is only through transfer due to Mnemonica skill that it may become so. Appointing a Lieutenant is something you do at the end of a turn in which you spent Loss of Lieutenant.
