There is an image of this cultivar on the Hosta Library. From the photo on the HL website, it appears to be a large size hosta with drooping, dark green leaves with chartreuse medial (center) variegation. This sport of H. 'Niagara Falls'  is a non-registered cultivar which was originated by Hans Hansen and Walters Gardens, Inc. of Michigan. 

H. 'Angel Falls' is described in the patent application as "the reverse color pattern mutation from 'Bridal Falls' U.S. Plant Pat. No. 25,594 where the leaf variegation has switched positions."

The patent application also lists the following as similar cultivars: ""Compared to the sport parent, Hosta ‘Niagara Falls’, the new plant, is smaller in habit and has leaves with that emerge with creamy yellow centers that develop to a creamy white to near white and sinuate or undulate margins of dark green margins. The flower scape generally greyed-yellow colored on the new plant rather than olive green. Compared to 'American Hero' the new plant has more arching foliage with stronger sinuate to undulate leaf margins. 'Satin Doll' has similar shaped foliage, but the margin is not as sinuate to undulate as in 'Angel Falls'. Compared to 'Guardian Angel' the new plant has foliage that is more sinuate to undulate, and the center leaf color of 'Guardian Angel' is viridescent rather than albescent. 'Cyclone' is a smaller plant, has smaller leaves with leaf centers that are more white in the spring, and without the arching habit and lacks the sinuate to undulate margin. The new plant is larger in both height and width than 'Greenhead Center Court' and also has a more cordate leaf base and more sinuate to undulate margin. 'The Queen' is smaller in habit, has flowers that are deeper lavender, stiffer more upright foliage and less sinuate to undulate margins.