This was already sent as a comment in another thread but I decided to post here for awareness.
As of this post, the latest Flash Projector (what you use to run RotMG standalone) version is v24. Older versions (v15;v16;v17;v18) will guarantee a more stable FPS to your game because they don’t have unnecessary functions that RotMG will not take benefit of - so they just end up slowing you down.
#1stly:
Google “flash projector download”
#2ndly:
Go to your specific OS version (Windows, in my case)
Right click the “Download[…]projector” and copy the link/URL
Follow to next step
#3rdly:
Paste the link somewhere, as of this post the last one is:
“https://fpdownload.macromedia.com/pub/flashplayer/updaters/24/flashplayer_24_sa.exe”
Change the numbers to the desired version:
“https://fpdownload.macromedia.com/pub/flashplayer/updaters/18/flashplayer_18_sa.exe”
And open that link to download it. I’m currently using version 18, I’m not sure if older versions will help more with fps, but I’ve seen people use version 14 without any problem.
Hope this helps!