Mortal Kombat 9 (2011): Easy Koins
In Mortal Kombat (aka Mortal Kombat 9, 2011 version) for the PS3 and Xbox 360, you get Koins while playing Story Mode and Arcade Mode that you can use to unlock alternate costumes and to unlock fataties and other extras in the Krypt.
The easiest way I’ve found to get Koins in Mortal Kombat is to set the difficulty to Beginner and set the number of rounds to three. On Beginner, it is extremely easy to get flawless victories which will give you 1000 koins per round, followed up by fatalities which will give you 250 koins per match. Check out my other guides for full lists of Mortal Kombat fatalities if you don’t know them.
Tip: Use a character that has long ranged moves, like Scorion’s spear, or Liu Kang’s fireballs and flying kick. On Beginner, the opponent will rarely block in the first few matches, so you can pretty much have your way with them, with very little risk. Once your opponents start to get tougher (even on beginner they start to get tougher up the ladder), then simply start Arcade Mode over again and repeat.