How do the chance for +% lightening skill work?

How do these work if you have several of them?

Like if i had

20% chance for +100%
15% chance for +150%

Do they roll independently and just add that value to the lightning damage if roll is successful?

Yes.

567890

they roll independently, and just add that much to your lightning multiplier if it goes through.

It’s part of why Lightning has the highest crit potential, because not only do you have Stormcaller’s pact crit amplifier, your innate damage type varies it’s damage between the extreme’s of it’s high and low, and it also has extreme’s multipliers.

Cool thanks. Is it just for auto attacks or spells which do lightening too?