Core Items..
Adagio comes with a bonus health ratio on his Gift of Fire heal, so it’s recommended to be building a lot of health on him. Because his heal can only affect one ally, rush Fountain of Renewal first. Crucible has a boatload of health and will ensure you land Verse of Judgement if the enemy can stun you; if not, it still makes for a good team-wide item. Contraption comes with health and cooldown speed, allowing you to give stronger, more frequent heals. Shatterglass will increase all of your abilities effectiveness enormously.
As Needed..
War Treads are typical to build on supports, and especially important on Adagio due to its bonus health. Stormcrown provides a solid amount of damage and cooldown speed, making it a good purchase. Consider building an Atlas Pauldron if you’re against a hero that relies on attack speed such as SAW, Ringo, or Krul. Keep in mind landing the debuff requires thought-out positioning. Alternating Current can be a good damage item to pick up, and works well with Adagio’s B, Agent of Wrath. Broken Myth will increase the stats on all of your abilities throughout a fight, and is perfect if you want to be finishing a fight off with Verse of Judgement.