The Happy Ghast can ride minecarts, even though it should be very obvious from looking at it that its model should not be able to fit inside the minecart. This also has the side effect of making it difficult to free a ghast that has gotten stuck in a cart, as the minecart’s hitbox is inside the ghast's hitbox. For reference, they already cannot ride boats.
This is similar to MCPE-161197 (which is marked as Fixed), but affecting the Happy Ghast (it wasn’t yet added in the game at the time that issue was made).
To reproduce:
Summon a Happy Ghast in creative mode.
Run this command:
/execute at @e[type=happy_ghast,c=1] run summon minecart. The ghast will ride the cart you just summoned, and will fall downward.
Comments 2
Thank you for your report!
However, this is confirmed to be Working As Intended.
This is however a valid request and an be raised as such in our Feedback Site or Discord.
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All mobs can ride in minecarts. The issue you mentioned (MCPE-161197) is about boats and does apply to happy ghasts because it based on mobs' collision, not a list of mob names.
It is not difficult to remove a happy ghast, or any other large mob, from a minecart. You put it on an activator rail, and power the activator rail. Or you leash it. Tutorials for happy ghast docking stations are easy to find, if you need help with the mechanics.
The change to make large mobs unable to fit in boats is already unpopular because it makes transporting mobs like horses and pandas across water much more difficult. If the ability to trap large mobs in minecarts were removed, it would ruin a lot of creative builds like docking stations, mob traps, ravager-based crop farms, and ghast blasters.