Ushanka

Use the Arrow Keys to move. Press SPACE to jump, and hold SPACE to jump further. Press P to pause.

When you get the artifact, press D to go between different dimensions! Both dimensions have their own set of obstacles, so make sure you time your movements just right when switching between the two.

HINT: You may have to fall through some barriers when going down a tunnel. If you can't break a barrier, try going higher up by wall jumping and then fall to break it!