>>532175012
I think that's how it works in the open world but I don't care enough to check, the most important bit is the Stygian version works differently if the datamines are to be believed
I think the open world one just keeps increasing until you eventually reach the max (where it goes into the shield mode) but the Stygian version will apparently lose a set amount of charges every second, presumably because it has far more health than the regular version
It seems like you're meant to try to balance infrequent hits with high damage in order to prevent filling up the gauge entirely, so Mualani will probably be really good here and based on the current first iteration of SO it's painfully obvious they want to tailor and select the bosses specifically based on which characters that are running on the banners

We'll see what people end up doing once it goes live