it often sees play in cEDH, where decks dump it into play turn 2 or 3 for a surge of mana

A Little Chat Abigale, Poet Laureate Aboleth Spawn Absorbing Man Abyssal Harvester Activated Sleeper Adagia, Windswept Bastion Adventurous Eater Aethertow Agate Instigator Agrus Kos, Eternal Soldier Altar Ibn-La'Ahad Altered Ego Amphibian Downpour Amphin Mutineer Angel of Indemnity Angel of Sanctions Anhelo, the Painter Anikthea, Hand of Erebos Anointer Priest Applied Geometry Araumi of the Dead Tide Arboreal Alliance Arcane Artisan Arcane Heist Arcane Proxy Arcane Savant Ardyn, the Usurper Arna Kennerd, Skycaptain Artisan of Forms Ashad, the Lone Cyberman Ashling's Command Ashling, Flame Dancer Ashnod the Uncaring Assemble from Parts Assembly Hall Assimilation Aegis Astral Steel Audacious Swap Aurora Shifter Auton Soldier Aven Wind Guide Back from the Brink Banish into Fable Banshee of the Dread Choir Barkshell Blessing Baron Helmut Zemo Barroom Brawl Battle for Bretagard Battlemage's Bracers Beamsplitter Mage Belonging Benthic Anomaly Bifurcate Biowaste Blob Blade of Selves Blade of Shared Souls Blazing Firesinger Bloodforged Battle-Axe Bloodthirsty Adversary Blue Mage's Cane Blue Ribbon Blue Sun's Twilight Body Double Bramble Sovereign Brass Knuckles Brenard, Ginger Sculptor Briarblade Adept Brigid's Command Broodbirth Viper Brudiclad, Telchor Engineer Burn Trail

Unbreakable Formation Speaking of, Unbreakable Formation is the best of the white 3- and 4-mana spells that protect your whole team, mostly because the main phase addendum can turn this into a game ender
Even better, being able to untap four creatures lets you tap out during your turn to add bodies to the battlefield and then still cast a counterspell during your opponent's turn, potentially for free, which is super strong
This card is a delightful reference and exploration of that two-part experience