What happens if i insert 30 yellow gems on the Pot on Nazarene Tower?

[snakedometalgear]

I’ve been on this map for some time. It is a very interesting map, at the end of it, when collecting fragments of dark orbs, you can get the key to a chest on the north. In another place there is an object that if I put 30 pieces together, I get a 5 minute buff(ok…? i really dont get it). And in another there is a vase, pot, that if I put 30 pieces of yellow gem (which is relatively rare) … what happens? Will it be worth the effort?

thats the pot

[venetiansnare]

never got 30 in here but i figured it spawned mobs or something
I know how to open the chest though if you curious about that

[venetiansnare]

there’s also a weird interaction with the altar at the bottom that gives you a buff against monsters

[Yuukikami]

iirc it spawn alot of terra mobs with spears. nothing much