Movement of Fish-like Creatures while on Land (5e Variant Rule)
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Movement of Fish-like Creatures while on Land
Sometimes, you want merfolk to come on land or you have a weird PC that insists on being a mermaid, but you have a campaign that mostly happens on land. Then this rule should help you out.
It’s quite simple:
- If a creature that normally uses a tail to move forwards, tries to move on land, it is always considered to be prone. This means that every foot takes an additional foot of movement, making it three feet of movement while in difficult terrain. Always use their swimming speed to determine their speed while prone, as they have an easier time moving prone than most land-based creatures.
- If such a creature wants to stand upright, it must use all its movement to do so and it must move at a quarter their swimming speed, or fall prone at the end of their turn.
- Any checks that are made against falling prone are made with disadvantage.
The standing upright land speed of an aquatic creature is then 1/4th of their swimming speed, like the merfolk in the SRD.