How does the ‘Keen Edge’ ability work

guild-wars-2

On my Ranger I have an ability called 'Sharpening Stone', as follows;

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I also have a trait called 'Keen Edge', which is supposed to trigger Sharpening Stone automatically whenever I reach 75% health – according to the text;

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However, I have never seen Sharpening Stone go on cooldown unless I have specifically used the ability. Is this how Keen Edge is supposed to work, or am I missing something?

Best Answer

Keen Edge (and other similar "Use [ability] when [X happens]" traits) grant you the effects of Sharpening Stone for free, automatically, when your health drops below 75%.

It doesn't matter if your actual Sharpening Stone ability is on cooldown, or even if it isn't on your action bar.