Permanent Potion of Flying (5e Equipment)
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When you drink this potion, you gain a flying speed equal to your walking speed indefinitely and can hover, making this potion INCREDIBLY broken. However, effects that prevent spells from being cast stop this effect from working temporarily as long as your are under that effect (after the end of which the flight returns at the start of your next turn), and effects that end spells such as dispel magic disable the flight until the end of your next turn. If you have no other way to stay aloft when the effects aren't active, you fall. If you are hovering when you fall unconscious by any means, you stay afloat unless some effect disables your flight. (This theoretically means you can sleep in the air, which is one heck of a party trick.) If your flight is disabled while you're unconscious, you do not start to fly again until you are consciously able to decide to fly.