[Kromm]

Please note that only Regular spells have increased energy cost for target SM > 0. Area spells limit size affected through area affected instead of using the SM-based multiplier. Casting a Regular spell on an SM +1 target, you have to pay 1 + 1 = 2 times the energy. Whereas an Area spell always has the same cost for a given radius . . . but, say, an SM +1 target that occupied three hexes, like a horse, would poke out of an Area spell with less than a 2-yard radius, so you'd need to cast it over a 2-yard radius to affect such a target.

Legalistically, note that paragraphs 2 and 3 of Area Spells (p. B239) specify how energy cost works for Area spells. Paragraph 6 ("Otherwise, Area spells work like Regular spells.") comes at the very end, so its "otherwise" means "except as noted above." Thus, paragraphs 2 and 3 override the Regular spell energy cost rules, and it's canonically wrong to charge a wizard, say, ×3 for a 3-yard radius and a further ×2 to affect up to SM +1. The wizard pays only ×3 cost, and any creature of any SM that's mostly within the area is affected. Size only matters indirectly, in that huge targets won't fit into tiny areas.