At MinecraftOnline it is possible to collect the heads of players you slay in PvP. You can then place these heads as decorative blocks in the world, taking trophies of your enemies.
To ensure fair play and to discourage abuse, there are certain restrictions in place:
- You can only collect one head from each player within a two-week period.
- You cannot collect the head of players who have been on the server for less than 4 hours.
- A log of every head you collect is kept, and is searchable by the admins.
- Every head placement and breakage is logged. Stealing heads placed by other players is grief, just as with any other block.
Loading in player heads (whether it is placed or stored in chests) will cause lag from fetching skin caches, and as such, storing excessive amount of heads in one place is highly not recommended. Sometimes heads load but on the default Steve/Alex skin. Try reloading graphics or the chunk if this happens.
Head Corruption Bug & Prevention
As of the 1.12 update, a bug has been found which turns any player head into a Steve/Alex skinned-head if it were not placed before X amount of time elapses (X = likely server restart, or ending the player's session - to be determined).
Whilst remaining in the inventory, the head is in a dynamic state and grabs the skin every time it is loaded. For unknown reasons, placing the dynamic head in a container (chest etc.) or leaving it in an inventory (including armour stands) for X amount of time prior to placing the head will cause them to corrupt.
In order to prevent this bug from happening, heads should be placed down soon after they are obtained, so that the player's skin data is stored in the head itself.
There is currently no fix to this bug - see the Gitlab bug tracker for more information: https://gitlab.com/minecraftonline/sponge-update/-/issues/246
There is also an issue where heads lose its skin when placed due to target player having changed its name. This is likely due to heads searching for the player name and not their UUID, a system which will have been changed in Vanilla Java 1.13+. If this happens, server cannot find the target username and the skin is updated to null (Steve/Alex). Avoiding placing heads of whose changed their name is not advised, but do be aware of the lag.