Tier: Tier 2
Color: If two-toned, the center OR outer ring is any color natural to the base, while the other part must be darker or lighter than the base. If three-toned, then only the middle fill color can be natural to the base, while the inner dot and outer ring must be lighter or darker than the base. The inner dot and outer ring can either both be lighter, both be darker, or one lighter and one darker.
Tones: Two or three toned
Shape: Circular/oval/tear/eye shaped
Holes:
Tapering:
Breaks: 
Symmetry:
Nuances: 
Edges:

Optional Marking Interactions
Eye Spots + Spotted
Allows eye spots to be anywhere on the body.
Python + Eye Spots
Allows for a handful of small blobby spots with outlines anywhere on the body except the hands/feet, muzzle, whiskers, and chest. Counts as Tier 3, may be any color natural to the base, with no gradient allowed.
Eye Spots + Leopard
Allows Eye Spots to be all over the character without a restriction on number of rings or color, but cannot be too dense and must be fairly spread out. Has Leopard's minimum range. Can have the occasional break in the rings as long as it's the minority.