On the extra stage Reverse Block,
bring a void wispon to beat enemies and collect rings at the same time, if you have the one with the ring boost for enemies defeated, use it.

You also want to be using the Bird class
so you can double jump and skip the platforming part.

You should be able to finish the stage in 20 seconds if you do a perfect run which isn't hard to get used to. Otherwise it should take between 20-25 seconds if you make some minor mistakes. Sorry for no video, I would publish one but I instantly uninstalled this piece of ♥♥♥♥ game after getting this achievement but I figured I should leave this out here in case anyone can use this. I know your pain.

You should be getting close to 400 rings per run if you use the Void wispon with the ring boost. I would recommend this method over the hover strat on Stage 25 / Imperial Tower. With that you can get 999 rings per run which took me like about 1min30 every time. This method gets you 1600 rings every 1min20 assuming you can do 20s runs, or 1200 rings every 1m30 if you do it in 30 seconds. Both are better in general.

Anyways that's about it, hope somebody can use this guide to get this miserable achievement faster while waiting for Frontiers to come out. Hopefully that game isn't ass either lol.