The remaining 2 pieces of the series.
World 3 was dominated by water and featured the Frog Suit. I felt it was essentially useless when not under the sea but they made a big deal out of it in the cartoon series when it was raining. A plumber who can breathe underwater doesn't really need these abilities. Water Land also contained a strange canoe that could be used to freely roam the map. No doubt this was the inspiration for Wind Waker.
World 8 features Dark Land and a fire ballin' Mario. Everything was dark, depressing, or on fire in this world. Bowser also had a tank.
Both are available as prints at Society6