March 7th is an Ice-element character who follows the Path of Preservation. She excels at shielding a single ally and launching counterattacks whenever shielded allies are attacked. Her Ultimate deals AoE Ice damage with a 50% base chance to inflict Freeze.
March 7th performs well in early-game content but struggles in tougher endgame challenges. Since her shielding only targets one ally, she becomes less effective in difficult modes like Divergent Universe and Simulated Universe, where consistent team-wide protection is often needed.
Best Cavern Relics
(2) Increases DEF by 15%.
(4) Increases the max DMG that can be absorbed by the Shield created by the wearer by 20%.
This set is especially effective because her shield strength scales with her DEF.
Best Planar Ornaments
(2) Increases the wearer's DEF by 15%. When the wearer's Effect Hit Rate is 50% or higher, the wearer gains an extra 15% DEF.
This is currently her best Planar Ornament set, as it further increases her shield strength. Since March also needs Effect Hit Rate, reaching 50% not only helps her land Freeze more consistently but also grants additional DEF, further improving her shield absorption.
Best Stats

Body
DEF%

Boots
SPD

Sphere
DEF%

Rope
Energy Regeneration Rate
Substats
DEF% / Effect RES / SPD / DEF
info
For March 7th, prioritize DEF% as her most important stat since it directly boosts her shield strength and counterattack damage. In the Body slot, choose DEF%, while the Feet can be either DEF% for tankiness or SPD to take more turns. The Planar Sphere is flexible, with options between Ice DMG% for stronger Ultimate damage or DEF% for pure shielding. The Link Rope works best with Energy Regen Rate to cycle her Ultimate faster or more DEF%. For substats, focus on DEF%, Effect Hit Rate (ideally around 40~50% to reliably Freeze enemies), SPD, and Flat DEF.
Best Light Cones
SourceLight Cone Event Warp
All-In
Increases the wearer's DEF by 40~64%. When the wearer provides a Shield to an ally, the wearer's CRIT DMG increases by 40~64%, lasting for 2 turn(s). When the wearer's follow-up attack hits an enemy target, there is a 100~160% base chance to increase the DMG taken by the attacked enemy target by 10.0~16.0%, lasting for 2 turn(s).This Light Cone grants her buffing ability whenever she provides a shield to an ally.
SourceStellar Warp, Light Cone Event Warp, Starlight Exchange, Stellar Convergence
Verdict
Increases the wearer's DEF by 24~40% and Effect Hit Rate by 24~40%. Increases the chance for the wearer to be attacked by enemies. When the wearer is attacked, increase their DEF by an extra 24~40% until the end of the wearer's turn.This Light Cone provides DEF and Effect Hit Rate for March, increasing her chance to apply Freeze with her Ultimate. However, it also raises her aggro, which can make it harder to decide whether to shield herself or her allies.
SourceStellar Warp, Departure Warp, Character Event Warp, Light Cone Event Warp
Time Fleets Away
The wearer is more likely to be attacked, and DMG taken is reduced by 16~24%.This Light Cone is effective for drawing enemy attention to her while also reducing the damage she takes.
New Chapter
Increases the wearer's DEF by 16~32%. Increases the DMG of the wearer when they use their Ultimate by 60~120% of the wearer's DEF. This effect only applies 1 time per enemy target during each use of the wearer's Ultimate.This is a good alternative Light Cone designed to increase her DEF.
SourceStellar Warp, Departure Warp, Character Event Warp, Light Cone Event Warp
At This Very Moment
Increases the wearer's DEF by 16~24%. After entering battle, increases All-Type RES of all allies by 8~12%. Abilities of the same type cannot stack.This is also a good alternative Light Cone, designed to increase her DEF and provide team-wide DMG RES until the end of the battle or until March is knocked down.
Sweet Dream
Increases the wearer's provided Shield Effect by 12~24%. When an ally target has a Shield, the DMG dealt increases by 12~20%.This Light Cone enhances the shields March provides and boosts the damage of shielded allies.