See this video: https://www.youtube.com/watch?v=Lny6Ri7y_y8

Command used in the video:
/summon phantom ~ ~10 ~ {Size:5,Passengers:[{id:"pig",Saddle:1,ActiveEffects:[

The Bug

While riding the entity summoned by the command above and than killing all the entities exept for players, the internal server of a single player world is shut down, similar to the elytra glith in MC-122354, but the disconnection is faster and the player is unable to enter the world anymore.

How to Reproduce

1. Sommon a ridable phantom using the command above.
2. Ride it.
3. /kill @e[type=!player]
4. Say goodbye to your world.