In variants with percentage-based intrinsics, see invisible is no longer a binary attribute. Eating invisible stalkers now gives you various percentages of the intrinsic. While extrinsic see invisible still works like it does now, allowing you to see any invisible monster in line of sight, intrinsic see invisible shows you invisible monsters in line of sight within a certain radius from you. The radius increases with the percentage, possibly the square root of the percentage (so 64% see invisible is a radius of 8, and 100% is a radius of 10 - note that 100% still is less powerful than extrinsic see invisible’s unlimited range).