Question about Ascendants

I am reading memories of ice rn (Rake just joined the camp of the 2 armies) and so far I can follow everything but there is one thing I struggle to grasp and thats the strenght of Ascendants and similar beings. Like how they fit with mortals and armies in strenght. From the way he is described beings like Brood should be able to fight off whole armies. Beings that can shatter mountains, and yet the Malazan army fought his army loosing despite seemingly not having ascendants (as far as the books revealed), he either didn't fight himself or held back if I get his power right.

or is being an Ascendant not directly related to strenght but more a state of being? Could a mortal reach the same strenght without ascending? It seems Kallor wasn't an ascendant before he got cursed by the elder gods

it's a hard question bc I also don't wanna research too much out of fear to spoil myself so I hope there is a way to answer these doubts without spoilers