Gelibord lightning

There's an NPC in Gelibord who says that every night, he hears lightning strike the same spot. To my knowledge, every night at midnight, lightning is supposed to strike in Gelibord's graveyard, causing a grave to open. I waited, but nothing happened during the whole night.
So, was this removed? The grave that's supposed to open is still there (the one with a wither skeleton skull on top).

 

When the grave opens, what does it reveal?

 

I think it's supposed to reveal an underground room of some sort, with a mob that drops a special item or just a Tier 4 loot chest.

 

I might be misremembering this, but I feel like there used to be a Thunder (maybe?)"Powder Altar" in there.

from the wiki:

• Until the 1.17 Dungeons & Discoveries Update, in which Relics were replaced by Discoveries, Powders could be obtained from the various Powder Relics spread across Wynn and Gavel.

 

Yep, you're right! Check out this thread, apparently the graveyard used to house the Tier 5 Green Powder Relic.