Level 1. GOD, DOG, GOLD, OLD
Level 2. FIR, FAR, FAIR, AIR
Level 3. ROD, ROW, OWL, LOW, WORLD, OLD
Level 4. SEA, ASH, SAKE, SHAKE, ASK
Level 5. LIE, LIFE, FIRE, FILE, FLIER
Level 6. RIM, IRON, MINOR, NORM
Level 7. SING, SIGN, SWING, WING
Level 8. LAB, ALE, BALE, BABE, BABEL, ABLE
