Good skill for Warriors and Palys. It is great for bosses like Kraken and Spider.
As a mage, you'd prob want to ignore it unless you're playing on easy and have a huge abundance in gold and can afford to buy the extra might runes. As a Paly, you'll have so many Might runes, you'll want to invest in it because they'd be sitting there (even after spending points on rage/tactics/onslaught/nighttime)
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