Search:

It's her mechanic. Read the tooltip. It says:
The Rank of her abilities will transfer to the skills of the god she copies. This ability's cooldown will be increased to match the target God's...

Hello,

Let's look at her lore:
Both beautiful and terrible, the Goddess Hel is keeper of the dead, lays judgment on souls, and decides who is reborn. She is both sides of two extremes.

So...