So it's not the Amps that get you, but the Coulombs? Or is it the Joules?
neither. even a shortcut saying like "total energy delivered" is not accurate, because it depends on how it is delivered and how it dissipates.
styropyro made a fascinating (if terrifying) video about it
Lethality of electricity is multi-dimensional, trying to reduce it to a single quantity does not really work (exposure time and electrical frequency are very important).