My guess is that was an early version of DA.
You can see he's using Shang and Cyrax's Straightsword weapon, not to mention the fact that his name is "Blind Kenshi" there. That was his origional name before it was changed.

Well they are probably early arenas of DA. But i remeber that there is one Arena when characters fighting in demo mode i never played in DA. That arena has trees but i have open all the koffins so, i don't know what that arena is.
But these two seems earlier arenas of DA (i think they are the Sarna Ruins and Shang Tsung Temple)

The two areas arenas that you speak are normal arenas that are in MK: DA. Serrea ruins is where Shang and Kenshi are fighting and Palace grounds are where Li Mei and Kenshi fight. You can tell that those parts of the video where Kenshi fights Shang and Li Mei are very early builds of MK: DA since Kenshi name is Blind Kenshi( Kenshi earliest name in MK: DA also by the graphics at as near a good as MK: DAs. The parts of the video you speak of are from Deadly Alliance.

haven't you played deadly alliance ?
those areas are unlockables

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