Its not rng.
3 melee damage is effectively 3 dps for a feral druid. If you want to convert that to attack power it becomes twice as much as the swift skyfire diamond, with the 1/100 chance of an interupt stun as well I guess, but thats not its main attraction.
I was on Al'Akir for a while and spoke a bit to Exerion, he is an amazing druid but he is also teamed with possibly the best rogue in Europe, and they are just owning it up on Blackout.
Anyways i swapped to this meta from 12 agi 3% increased crit damage, as I already have 48% crit self buffed (49.8% with idol proc) so I prefer the AP boost from the brutal earthstorm diamond.
Btw Ive never seen you on RH before Ifgenia, I played feral there since the start of the server
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