Letter on position 1 (p) changed: 12 words backs dacks hacks jacks lacks macks racks sacks tacks wacks yacks zacks Letter on position 2 (a) changed: 4 words pecks picks pocks pucks Letter on position 3 (c) changed: 3 words paiks parks pawks Letter on position 4 (k) changed: 4 words pacas paces pacos pacts