An extension by Peter Ward (@flowblok) of the [BackFlip][1] esoteric programming language.
Here follows the original description by @flowblok from the NCSS 2014 Programming Competition:
Nyan Cat is stuck in an arcade game! You have the feeling that she's trying to get a message to you, but the game is running so slowly it will take days until she completes her message. The game is played on a 2D grid. Nyan Cat enters at the top-left corner, and starts by moving one tile to the right every turn. Some tiles have things displayed on them:
- Arrows (
<
,>
,^
andV
): When Nyan Cat steps on one of these, it changes her direction so she is now moving in the direction the arrow pointed in. However, that arrow then changes direction to point back the way she came from.