Opal of unity

The void stone and celestial opal can be united by dropping one on top of the other. This will create a big explosion fusing the 2 stones into the opal of unity. This stone has the power of both stones. But it can destroy the pillars completely. There will be a 20% chance that the stone becomes unstable the player will have the throw the stone into the sky and hope that the 2 stones will one day fall back to earth.

Celestial opal: https://feedback.minecraft.net/hc/en-us/community/posts/360071796532-Celestial-opal

Void stone: https://feedback.minecraft.net/hc/en-us/community/posts/360071563191-Void-stone