Escape of the Unicorn - making animations

Making animations for Escape of the Unicorn

Size	Various: 8x8, 16x16, 32x32, ... , 64x64, but rather not bigger.
Background	Solid backgraund for the creatures' images for the walls or background tiles - no alpha, or defined colour.
# of frames	From 1 to 16, but more is not a problem.
Image format	PNG is prefered, others are possible too.
Naming standard	The names must be unique and because all files are placed in one directory: eounicorn/data/tiles/* More details of the naming standards: for walls and bg tiles for objects
Tools	Any suitable tools are welcome: pencils, pens, paints, scanners, drawing apps, 3D modelers etc. The final effect should be always the same: nicely looking animation of 2D tiles.
Animations	Depends of kind of the movement that the creature performs. Horizontal travellers should have 2 sets of animations: for left direction movement and for right direction movement (not always necessary, e.g. when the creature is directed to the screen, it has the same animation for both movements) Vertical traveller usually has one animation, but it also can have two different: for moving up and down.