[MC-176359] Riding a leashed stack of entities causes stack to fly upwards

The bug

If a stack of entities' height exceeds the maximum length of a lead (such as 5 or more adult Striders), riding the top one while leashed to the bottom will pull the bottom entity into the air. This, in turn, pushes the entire stack, including the player on top, further up. This cycle repeats indefinitely, causing the stack to fly higher and higher into the air.

How to reproduce

Summon in a stack of 5 or more adult Striders (such as with the command below) with the uppermost Strider saddled. Attach a lead to the bottom Strider in the stack, and ride the top one.

/summon minecraft:strider ~ ~ ~ {Passengers:[{id:"minecraft:strider",Passengers:[{id:"minecraft:strider",Passengers:[{id:"minecraft:strider",Passengers:[{id:"minecraft:strider",Saddle:1b}]}]}]}]}

Update

This bug was originally found using the Striders added in version 20w13a, because of their natural stacking and rideability. But, as pointed out by Marcono1234, this bug is present for any stack of entities. After some further testing, I've found that this bug was present back in the first snapshot the lead was added, 13w16a.

Linked issues

relates to 1

MC-176387 Fishing rod can reel in vehicle of player Resolved

Attachments

Comments 3

marcono1234 2020-03-26T22:31:32Z

This appears to be not restricted to Striders:

/summon pig ~ ~ ~ {Passengers:[{id:pig,Passengers:[{id:pig,Passengers:[{id:pig,Passengers:[{id:pig,Passengers:[{id:pig,Passengers:[{id:pig,Passengers:[{id:pig,Passengers:[{id:pig,Passengers:[{id:pig,Saddle:1b}]}]}]}]}]}]}]}]}]}

So this is not a duplicate of MC-176032. However since multiple Striders can rider each other naturally it might be a pig problem there, see MC-176028.
Marking as related to MC-176387 since there the player is also pulling their own vehicle.

Are you fine with making this report more generic so it covers all entities? (But mentions striders as a naturally spawning example)

Volrix 2020-03-27T14:58:14Z

This is so hilariously specific. How did you just randomly decide to try this?

Noremac25 2020-03-27T18:23:08Z

I was watching Rays Works' recap of the 20w13a snapshot stream, where at 8:32 a player is seen holding a leashed stack of Striders. It reminded me of Breath of the Wild's Flying Machines and similar glitches in other games, so I wondered if such a glitch was possible in Minecraft. It turned out so, and that it has been possible for nearly 7 years; and this may be the first reported discovery of the bug.