sly vs guileful

sly and guileful both are adjectives.

Word	Noun	Adjective	Verb	Adverb
sly	No	Yes	No	No
guileful	No	Yes	No	No

As adjectives, sly and guileful are synonyms defined as:

Other synonyms of sly include crafty, cunning, dodgy, foxy, knavish, slick, tricksy, tricky, wily.

sly (adjective)	guileful (adjective)
marked by skill in deception	marked by skill in deception