Augusta — Among all options, Augusta is the most effective teammate for Iuno. When Iuno activates both her Full Moon Domain and Outro, the resulting amplification can reach 90%, creating one of the strongest buffing scenarios possible. This makes the Iuno–Augusta combination the most efficient and impactful pairing available.

Jiyan — Jiyan aligns extremely well with Iuno’s kit. His damage output relies heavily on Heavy Attacks, which Iuno enhances by 50% through her Outro. In addition, she contributes meaningful personal DPS, making the partnership both consistent and highly optimized.

Phoebe — Iuno integrates effectively into Phoebe-based teams. She can operate as a secondary buffer for Zani in Confession builds, while also reinforcing Absolution with her strong amplification effects. Although the benefit to Absolution is partially diluted, Iuno’s individual damage ensures that overall performance remains high.

Jianxin — She provides a 38% increase to Liberation damage on Outro while also supplying shields to the entire party. Her main drawback is rotation inefficiency, which limits her practicality, though her contributions remain valuable.

Changli — Changli is not the most optimal partner for Iuno compared to top-tier options, but her Outro buff still grants a Liberation damage increase that Iuno can utilize effectively. Both characters are capable of contributing significant personal damage, and while their synergy is not the strongest, they remain a viable pairing. Players who prefer using these two together can do so without major drawbacks, even if stronger combinations exist.

Yinlin — Yinlin is the second most suitable partner for Iuno in DPS compositions. She delivers consistent damage both on- and off-field while increasing Iuno’s Liberation damage by 25%. However, Yinlin’s effectiveness is highly dependent on proper investment and her exclusive weapon, Stringmaster, in order to outperform alternatives.

Zani — When paired with Zani, Iuno fulfills multiple roles. She can replace Mortefi in standard setups alongside Spectro Rover or act as the third member in Zani–Phoebe compositions, substituting either Shorekeeper or Spectro Rover. While not the optimal arrangement, it remains a viable option.

Ciaccona — Ciaccona serves as the top hybrid support option for Iuno in a DPS role. While her maximum potential requires her Signature weapon, even without it she provides steady buffs to Aero damage, maintains fast rotations, and supplements the team with solid personal output.

Rover (Aero) — Aero Rover provides exceptional support for Iuno as a DPS centerpiece. By completing their rotation, they deliver a reliable 26% Aero damage amplification for the entire team. In addition, Rover raises the maximum Aero Erosion stacks when used with Ciaccona, and functions effectively in a lineup with Jiyan and Iuno by balancing buffing, healing, and additional personal output.