Will it be alright if I kill the Wither Boss under the bedrock portal in the end? Or is that cheating? Just to know...

That's impossible on bedrock. You can do it at the bottom of the nether but i thinking only old versions It's easy btw: Killing wither on bedrock (suffocating) - Gliched Killing wither trapped in obby - Glitchless

Ohhh so that counts like a glitch?

You can do it I think one of the best speedrunrs did that so I think it’s ok

its allowed to spawn it in obsidian (ex. building a cage yourself using 6 or more obsidian/spawning it inside an obsidian pillar) but spawning it inside bedrock counts as a glitch

@EmiCh321 you can spawn it below the bedrock portal but you need a bit of obsidian and a specific place to spawn it

Yeah bcz glitchless would be like making an obisidan box of like 13+ Obsidian first do obsidian then put souls sand and wither skulls (ik u know it I'm just saying this bcz it might help some people) then just place tnt and have a hole and obsidian floor then explode it and put obsidian in the hole tadaaaa Glitchless%