Also, an honorable mention goes to Abeyance, which doesn't look like much today, but its original wording basically made it a mono-blue Time Walk back in 1997
25 Spells Engineered Explosives Mishra's Bauble Deathrite Shaman Elves of Deep Shadow Traverse the Ulvenwald Thoughtsieze Fatal Push Grim Flayer Tarmogoyf Bitterblossom Satyr Wayfinder Grapple with the Past Collective Brutality Grisly Salvage / Vessel of Nascency Smuggler's Copter Abrupt Decay / Dissenter's Deliverance Liliana of the Veil Maelstrom Pulse Eternal Witness Recurring Nightmare Ramunap Excavator / Jadelight Ranger Ravenous Chupacabra Ishkana, the Grafwidow Nissa, Vital Force Emrakul, the Promised End 15 Lands Mostly you want to keep a delirium deck pretty streamlined
Gishath, Sun's Avatar, Tana, the Bloodsower, Samut, Voice of Dissent, I could go on but basically a ton of Gruul decks can benefit from Rhythm of the Wild
By the way, if youre curious about the solution to this puzzle, you can find it here