Hello b98andrei:

Skill stone event is not a very frequent event. Yesterday we had summoning chance x2 event plus free holy bonds summoning epics/holy event.

I hope the one you are mention is coming next... it usually does!

Hello vanesamei 🙂

I ask because last time when i saw that event was in october. after a new event appeared-overlord tournament- the skill stone event disappeared. in february 2021 the algorithm was  skill stones event 2 times/month. now... what is the algorithm ?

In this 3 months all guardian events were repeated without skill stone events. 

Hello b98andrei. As vanesamei already told, these events won't be so often anymore. We didn't get any info that these events are deleted. So, eventually, we will get them. Moderators don't know anything about the algorithms so it is not possible to know when this event will appear. I don't upgrade my guardians as well, as I'm waiting for this event as well. Stay tuned 🙂

Hi Katia Maurogenous !

I understand. Thank you very much for your answer. I appreciate ! Good game !