I'm getting ready to run Icewind Dale: Rime of the Frostmaiden and one of my players is going to be a centaur. Reading over the rules about travel, I see the talk of snowshoes and I have to wonder if the centaur could use them or if they would do any good for a horse like creature. I can't find a ruling anywhere about this, not surprised since it's a very unique situation, and I'm not sure how to base any ruling on it.
[RPG] Would a centaur benefit from snowshoes
centaurdnd-5eequipmentrime-of-the-frostmaidentravel
Related Solutions
One dot marking the roads between towns represents 1/4 of a mile.
I've verified this using microsoft paint. First, note that 1 mile is 63 px wide:
Next, I found the nearest-to-horizontal stretch of road, just east of Torgos and measured four dots:
Also 63 px wide.
So four dots on the roads represents one mile, or 1/4 of a mile per dot.
Note, astute readers will be keen to avoid a fence post error; the 63px segment consists of exactly four whole circle diamaters.
Both bullet points take effect, but the second one is vacuous.
In its title and in its body text, the question explicitly asks about what happens if you are frightened of yourself. This is exactly what I am going to answer. Whether casting the cause fear spell on yourself (intentionally or by Spell Turning) becomes a non-issue because being frightened would cause you to lose your concentration on the spell immediately, would be a different question.
Considering the first bullet point: The crucial question here is: is a creature considered to be within its own line of sight? The only precise definition of line of sight is given in the context of the optional rule of playing on a grid (DMG, page 251, emphasis mine):
To precisely determine whether there is line of sight between two spaces, pick a corner of one space and trace an imaginary line from that corner to any part of another space. If at least one such line doesn't pass through or touch an object or effect that blocks vision -- such as a stone wall, a thick curtain, or a dense cloud of fog -- then there is line of sight.
The word another seems to prohibit using this definition in order to decide whether there is line of sight within the same space - which would be the relevant case in this scenario.
In the absence of a general mechanical definition of line of sight, we will have to go with its plain English meaning. I just tried around a bit, and I find it difficult to move my body naturally without seeing any part of it (or the clothes I'm wearing), unless I close my eyes. In fact, no matter where I look, my nose and part of my beard are always in my peripheral vision. It takes active effort not to see any part of my body, so I'd find it rather unnatural not to consider a creature to be within its own line of sight. Being the source of its own frightened condition, it should thus be subject to the consequences of the first bullet point.
Note that this interpretation of line of sight is consistent with the rules on Targeting Yourself with a spell (PHB, page 201), as is discussed e.g. here, here, or here (thanks to NautArch for referring me to these questions).
Considering the second bullet point: Since there is no additional condition in this bullet point, it definitely takes effect. The only remaining question is whether it actually makes a difference. "Moving closer to something" is obviously supposed to mean "reducing the physical distance to something", not some metaphorical or spiritual distance, or whatever other notion one could come up with. The rules on movement in combat say:
On your turn, you can move a distance up to your speed.
This seems to equate the distance to something with the movement it takes to get there. Since staying exactly where you are costs no movement at all, the distance to yourself is therefore 0. As a negative distance is impossible, no conceivable move could bring you closer to yourself than you are at the moment. Consequently, you cannot move closer to yourself - regardless of whether you are frightened of yourself or not.
However: That said, I think your ruling sounds much more reasonable, more in line with the idea of the frightened condition, and simply more fun than sticking to this strict reading of the rules.
Best Answer
First, the rules for snowshoes don't actually exclude their use by horses or centaurs; the rules make no mention of needing to have humanoid feet to wear them. I personally feel it would be poor DMing to just decide that one PC can't possibly keep pace with the rest of the group -- if one PC has to go slow, then the whole party has to go slow, at which point you might as well just forget that snowshoes even exist.
There's no physical reason snowshoes wouldn't work for a centaur. The whole point is to spread out the creature's weight across a wider area to reduce the amount that they sink into snow. Putting a wider base under a hoof would work just fine. While a horse weighs a lot more more than a man, it also has four feet instead of two, so that weight is already more widely distributed. Putting a platform under each hoof will work very well to keep them on top of snowdrifts.
But even better, there is a historical precedent for this -- horse snowshoes actually exist! For an example, this 1555 woodcut from a book by Olaus Magnus depicts a merchant and his horse crossing the mountains in Norway, both wearing showshoes.
They were usually made from wooden planks instead of a rawhide netting we're more familiar with, but anything that spreads out the weight should be fine. Here's an actual equine showshoe from the Norwegian Forestry Museum: