Phasing can also effectively remove an attacker from combat, giving this land a lot of extra utility beyond just tapping for mana
Even the smallest person can change the course of the future and the fate of Middle-earth is in your hands
For example, if four permanents have exalted, the creature that attacks alone will get +4/+4 to its stats

Alpine Grizzly Ashcoat Bear Ayula, Queen Among Bears Balduvian Bears Bear Cub Bosco, Just a Bear Copper Host Crusher Diregraf Scavenger Doc Aurlock, Grizzled Genius Dragon-Scarred Bear Drover Grizzly Druid's Familiar Duskana, the Rage Mother Evercoat Ursine Exuberant Wolfbear Fiendish Panda Forest Bear Friendly Teddy Golden Bear Goreclaw, Terror of Qal Sisma Grizzly Bears Grizzly Ghoul Hei Bai, Forest Guardian Hei Bai, Spirit of Balance Hurska Sweet-Tooth Koala-Sheep Kudo, King Among Bears Lumra, Bellow of the Woods Mother Bear Owlbear Owlbear Cub Pale Bears Phantasmal Bear Platypus-Bear Professor of Zoomancy Rampaging Yao Guai Razorclaw Bear River Bear Runeclaw Bear Ruxa, Patient Professor Spectral Bears Spirit of the Aldergard Striped Bears Studious First-Year Surrak and Goreclaw Ulvenwald Bear Ursine Fylgja Ursine Monstrosity Vastlands Scavenger Vivien's Grizzly Werebear Wilson, Refined Grizzly

My verdict: The Ruby & Amethyst Shimmering Skies Deck is ideal for players who want to outwit opponents with combos while keeping constant pressure on the board
The other way to use it is to focus on a single player, dealing double the damage if the plan is to quickly take out the bigger threat