The bug:

After placing then breaking an end crystal the client-side is forced to wait for the server-side to register the break packet before being able to place a new crystal, when it can just send a new place packet right after sending the break packet.

This bug really slows down the placing and breaking speeds of players with high latency/ping. Not very good for Crystal PvP.

Steps to reproduce:

1. Get very high latency/ping on your server.
2. Place an obsidian block and an end crystal on it.
3. Break the crystal then immediately try to place a new one. You wouldn't be able to place a new one.

Solutions:

There are 2 solutions to solve this.

1. You can make it so that you are able to send place crystal packets through already placed crystals AFTER sending the break packet.
2. Or for an even more effective approach you can make crystals appear and disappear instantly client-side just like placing blocks on high latency/ping. This solution stops your latency/ping from being a factor of your crystal placing and breaking speeds.

Intended behavior

You are able to send place crystal packets right after sending the break packet one in all situations while having high latency/ping.

Actual behavior

You're forced to have to wait for the server-side to register the break packet before being able to place a new crystal.