OGL Sheet question - crit range for NPC

I have an NPC that I want to crit on a 19. Is there a way to add that to the sheet?
So it is possible, but a bit of an annoying process and not perfect. The NPC sheet doesn't have as much customization functionality as the PC sheet. Meaning you can't control all of the individual attributes of the attacks, such as crit range. In order for your NPC to crit on a 19 you will need to modify the CORE DIE attribute (it will become 1d20cs19 ), which you can find in the PC settings and then change back to the NPC sheet. As I said before, this is not perfect since it means that any d20 roll (skills and saving throws in addition to attack rolls) will now crit on a 19 and 20.
Well, he won't be doing any skill checks so this works well enough. Thanks.