Islandwalk : 6 cards Turning Islandwalk into unblockable : 3 cards Tap/Untap Synergy : 11 cards Deeproot Pilgrimage, Merrow Commerce, Kioras Follower, Kumena, Tyrant of Orazca, Lullmage Mentor, Merfolk Sovereign, Merrow Reejerey, Seahunter, Empress Galina, Murkfiend Liege, Twists and Turns // Mycoid Maze Although the optimal Merfolk Tribal commander for tap/untap strategy is Kumena, Tyrant of Orazca, untap strategy also works well in our Merfolk Tribal build too, either as support to our aggro strategy (untap is enabling our creatures to block even after attacking) or as an amplifier of our creatures with powerful tap abilities (among them is Kumena, Tyrant of Orazca as part of the 99)
The historic permanents have always been integral to the game and continue to get more support with additional releases
You can only have so many colourless lands in a deck before they become overly damaging and the alternatives are typically more powerful
Subsequently, Rev is better placed within existing theft-focused decks, such as those helmed by Gonti, Canny Acquisitor