It’s been over a decade since Frank Sweeney—now going by Frank Fox—last competed on The Challenge, but his exit from the 2014 Free Agents season continues to raise eyebrows.

Think you’ve got sharp eyes? Our today’s optical illusion is putting vision to the test! Hidden among rows of 58s and 85s is a sneaky pair of 55s—and only those with 6/6 vision are said to spot it.