Completed - Resolved
Beast den upgrade does not work if beast den has been previously sold
1) Build 3*3 beast den.
2) Sell all your beast den tiles.
3) Purchase "Beast Den Upgrade" from the veins of evil.
4) Build 3*3 beast den.
Although the central prop looks like the upgraded version, when you click on it, only Oculus and Skarg will be present in the menu.
Customer support service by UserEcho
We have found the cause and fixed the issue, expect the fix in the next hotfix
You people are fast.