i had a villager traveling on a minecart. as he reached my farm, a rail was suspended 3 blocks over the farm, which would force him to fly and land on the farmland. when he hit the farmland, he went thru and landed on the rails below. his head was moving back and forth thru the dirt, and was not taking damage. the point is he should not have gone thru the dirt.
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i no longer have a screenshot available as the farm has been built. let me try redescribing it.
imagine a long line of rails, with a villager in a minecart traveling on the rails. he comes to the end of the line where the minecart will drop down on the y axis a few blocks to land on farmland while still in the minecart. Below the farmland, one block, is a series of rails and hopper minecarts designed to pick up farm drops that the villager will be making.
As he hits the farmland while still in the minecart, the minecart and the villager fall thru the farmland and land on the rails one block lower, and travel up and down the rails. the minecart isn't stopped by the farmland while the villager is still in it.
does that help?
Ah, thanks for the explanation. This is a known issue which we're already tracking in MC-2714, hence I've resolved this ticket as a duplicate of that one.
The fact that the villager doesn't take damage is caused by farmland not being a full block and thus not being able to suffocate entities.
Please attach some screenshots. I'm unable to understand what you mean based on your description alone.