When a ghast has no AI ({NoAI:1}), the player can still push it, causing it moves a short distance.
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When a ghast has no AI ({NoAI:1}), the player can still push it, causing it moves a short distance.
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Minecraft 1.14.2 Pre-Release 3
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This issue is a duplicate of MC-65664, which is currently considered intentional (see the last comment on that report).