Around 40 minutes to beat, as shown in this unedited playthrough. This version was tougher than the PS3 version, which I completed right before this one. Because of that I had most of my practice from that version. The main thing that made this version harder is that its capped to the default 3 lives , instead of 5 lives I had the PS3 version set to. I also was unable to pause the game since I was running it on TeknoParrot emulator. There may be a way to pause on that emulator but its been a while. Its useful for arcade games that dont run properly on MAME.
Check out my unedited playthrough of the PS3 version here :
• Under Defeat HD Deluxe Edition (PS3) ...
The main challenge is the final boss. The game gives you 3 lives and unlimited continues. You have 3 lives to make it to the next checkpoint, basically. The final boss can be tough since I dont understand how to dodge most of his attacks in the final form, so I need to just tank it. That requires playing very well on the previous forms of the boss.
I left this playthrough unedited since showing the deaths makes it easier to see how the checkpoints work. It would be confusing with deaths edited out, for this game.
The final remaining port/version of this game that I havent completed is the Dreamcast version. I have to find a way to set up some macros on one of my controllers so I can leave it running and unlock Free Play on that version, but running up the playtime. I did this with the PS3 version.