Unfortunately the true ending is not after the defeat of Cyblin Lord, The credits level is an official level you can select from the main menu, and the credits level is the true ending confirmed by Ana(creator of the game) and Iyaz(developer who also runs it), and its the only level to return you to the main menu. If i included the secret level after you receive the game over and before retrieving the pixel stone, then yea, that would be silly to include in the any% run.

i apologize for the late reply, i forgot to check in on the page for a bit WOOPS

p.s the the proper name for the "Credits Level" is THE END, but we dubbed it credits level.

I hope you consider running the game, we need more times on here :) Be sure to join the PR discord if you havent already, thats the best way to get ahold of me or the devs