I am looking for help with the wording/setup of this section of a dungeon. The bit is just to get them to walk backwards for x amount of distance. 

The party gets through a section of relatively safe hall, when they come to the next section. This section of hall is lousy with traps (everything and anything to make them question moving forward immediately including flying characters). On a wall near the characters is a riddle that reads "Retreat is no longer an option, but moving forward will clearly see you maimed." If the players look back where they came from there is a wall now preventing going this way and moment while facing forward activates the traps (some for the puzzle to last, or all to end it with lots of lost hp).

Is this riddle clear enough to be fair? Looking for suggestions. 

Maybe focus on sight with the clue? 

 "To proceed unscathed, retreat must be faced." 

"Facing your problem causes agony, As you proceed, Look to the past for security."

I dunno. Personally, I don't see anything hinting that you need to walk backwards. It seems more like a taunt than a riddle or even a hint, at least to me. It also depends on how difficult you want it to be. 

Maybe something like:

"Advancing forwards evidently leads only to despair,

But can you go backwards, to keep your hands a pair?"

I don't know. I suck at writing these things at the right level. I just feel like the original was to oblique and not obviously a riddle to be solved.

"The more you take, the more you leave behind.  Keep your eye on me, and you may proceed."

The answer to the riddle is "footsteps".  If you tell the party when they enter the area that it's barren except for a layer of dust on the floor that they're leaving tracks through.  Then when they reach the riddle, they have the clues they need.  

"Make feet move where eyes cannot stare,

just as Orpheus lost his wife most fair,

and as fools regret instead of plan and plot,

have faith that heads turn where bodies do not."

It's not perfect, but I like it.

If you have a Rogue in the party or anyone who is likely to investigate the traps, consider how the traps activate. Surely, tripwires and pressure plates cannot be the answer, as those will trigger regardless of how a person is facing. Magic seems to be the only solution, perhaps, but then you can make obvious hints within the room, like a huge face on the other side of the room/the wall that just appeared, and the riddle should advise the adventurers to look away from/look at the face, respective to its position in the room. 

For example, if the face is on the wall that appeared behind them, the riddle can say something along the lines of "to see one's lord is to live", with the face being the face of whoever built the place. A prideful king, perhaps.

Suddenly I want to design a dungeon built around dril tweets. This, of course, would be the "face God and walk backwards into Hell" one

This guy has a bunch of puzzles for D&D

https://www.youtube.com/c/WallyDM

Perhaps consider having a skull, or visage of the grim reaper, on the wall which appears behind them.

Then say something along the lines of:

"Death creeps swiftly from behind,
keep him in sight and you'll be fine
But all the while, bear in mind
one touch is all you'll need to die"

Or something like that. The way out is to back away from Death, watching the whole time. You can add a panicked puzzle halfway by having Death move to behind a puzzle wall, so they can see his robes but can't see him, so they have to reveal Death to get around the corner. Have the room flicker and death disappear, it'll freak them out entirely! Or, have Death start following them, and have the corridor act like a maze of line-of-sight where you need to predict deaths movements. That's a lot more in-depth though!

Edit- further idea to this. They see the riddle, and will likely look behind them. There they see Death, moving slowly towards them. They become Frightened of Death (so cannot approach him), so now have the ultra-trap corridor ahead, and Death behind, getting closer. They might panic and run from Death, or they might take the approach to walk backwards, which does not set the traps off. If they sit and wait for Death, then they die - so perhaps have a proximity based save to avoid being forced to flee from Death and into the traps, to keep the characters from an unfair insta-kill! Have the corridor go around a corner so they have to work out how to keep death a safe distance behind but still see him (leave that to them, they will find their ways).

I know this doesn't really answer the question - but what is it with traps? For the money you invest in a hallway full of traps, you could instead buy a really good trap, a troll to guard the door, and a gourmet dinner for you and your wife, ten times over. 

If I were a dungeon designer, I'd have a hallway as suggested, and just post the solution: Walk backwards, and you won't trigger the traps. Then they'd trigger anyways. And at the end of the hallway, under the final trap, I'd have a single, slightly singed handwritten note that read: 

Yea, I lied. And I'll let you know I laughed while I did. Thing is, the restaurant went out of business, so now - after all the traps - you still have to face a really good look, and a guard troll. Good luck (no, not really, get out of my tomb your miscreants! There's nothing valuable here anyways, I donated all that was left after the traps, the lock and the troll to the Lost Pets Foundation. I didn't build a dungeon to protect anything, I did it because I'm old and bitter and spiteful. You've been warned.)

And then, of course, I'd have a really high DC lock, and some sort of undead supertroll.

"Sometimes to move forward we have to look from whence we came."