List of guileful synonyms and guileful related words.
Byzantine, Machiavellian, Machiavellic, acute, arch, artful, astute, cagey, calculating, canny, chiseling, clever, collusive, covinous, crafty, cunning, cute, deceitful, deep, deep-laid, designing, devious, diplomatic, duplicitous, false, falsehearted, feline, finagling, foxy, fraudulent, furtive, indirect, ingenious, insidious, inventive, knowing, pawky, politic, ready, resourceful, scheming, serpentine, sharp, shifty, shrewd, slick, slippery, sly, smooth, snaky, sneaking, sneaky, sophistical, stealthy, strategic, subtile, subtle, supple, surreptitious, tactical, treacherous, trickish, tricksy, tricky, two-faced, underhand, underhanded, vulpine, wary, wily