Mortal Kombat Defender Earth attempts to combine Mortal Kombat, Mortal Kombat II, Ultimate Mortal Kombat 3 and the Mugen Mortal Kombat Project.

Default keys are pretty simple. they are:

Right--------------- ( ► )
Left----------------- ( ◄ )
Jump--------------- ( ▲ )
Crouching--------- ( ▼ )

High punch-------- ( D )
Low blow-----------( F )
High kick----------- ( S )
Low kick------------( A )
Running ------------( V )
Defense ------------( E )

Mortal Kombat Defender Earth 3 does a great job doing what it intended to do. Getting used to the keys takes a bit, but they can be configured in the Options, Input Config menu or tap F1.