Carl's skill for marking placed explosives with triggers he can fire mentally from a hotlist.
Carl used Remote Detonator twice in Zockau. The first marked the timed trigger on his rocket multi-launcher, hidden against the inside of a hedge in the stairwell park. The second marked the string of Barrel Bombs he rolled into the alleyways along the pub row, and he added that trigger to his hotlist for a mental click.
He fired the first trigger to launch the missiles at Xindy, but never got to click the second — the barrels went off on their own when Chin'Dua's falling body knocked one over and its integrity collapsed.
The skill that lets Carl fire pre-placed explosives from a distance.