Why You Should Not Upgrade 5-Star Legion in Guild of Monster Girls

Do not promote or upgrade 5-star Legion in Guild of Monster Girls. Keep her at her baseline 5-star rank and leave her primary skill set unranked. Upgrading her star tier or skills alters her combat profile, introducing longer skill cooldowns and increased base Speed that break her high-frequency Extra Action attack loops.

Because the game lacks a character regression feature to undo promotions or skill upgrades, advancing Legion permanently reduces her damage output in extended encounters, dungeon bosses, and guild trials.

Why Upgrading Breaks Legion's Extra Action Loops

Legion's high damage ceiling relies on the Extra Action mechanic, which grants immediate follow-up attacks outside the standard team round counter. At her baseline 5-star state, her core abilities are lightweight, spammable, and carry no lengthy cooldowns. Landing critical strikes or basic skill attacks triggers follow-up actions that chain seamlessly into one another, turning Legion into a continuous offensive engine.

Promoting her or ranking up her skills replaces these baseline attacks with modified abilities. These upgraded skills introduce three distinct failure points:

Extended Cooldowns: Higher-tier skills require multi-turn recharge cycles, forcing Legion to spend turns waiting rather than attacking.
Stance Shifts and Prerequisites: Enhanced abilities impose mechanical restrictions that halt the automatic flow of attacks.
Diluted Hit Profiles: Some upgraded attacks convert single-target hits into split-damage effects that fail to meet the trigger thresholds required to grant another Extra Action.

Once these upgraded abilities are unlocked, automated and manual skill queues default to the modified kit, dismantling the sustained loop that makes baseline Legion effective.

Speed Tuning and Turn Order Problems

Promoting Legion permanently increases her base Speed, which ruins standard party turn order. In tactical squad setups, support units must act before your primary damage dealer to apply Critical Rate buffs, Attack increases, and enemy Defense Down debuffs.

Baseline Speed: Baseline 5-star Legion naturally acts after standard buffers and debuffers. Every attack in her Extra Action chain benefits from active stat boosts and reduced enemy armor.
Promoted Speed: Upgraded Legion gains enough Speed to move first in the round. She attacks un-debuffed targets with un-buffed stats, expending her initial burst potential before team support comes online.

Attempting to fix this desynchronization requires equipping gear with negative or suppressed Speed rolls, wasting equipment sub-stats that should focus on damage.

Recommended Investment Allocation

Keep Legion at baseline rank and redirect your progression materials into her gear and supporting squad members.

Investment Area	Recommended Action	Combat Reason
Star Rank / Awakening	Leave at baseline 5-star	Preserves original skill set and keeps base Speed lower than buffers.
Active Skill Levels	Keep primary cycle unranked	Prevents added cooldown timers, stance shifts, and altered hit counts.
Equipment Stats	Prioritize Critical Rate and Attack %	Satisfies Extra Action critical strike conditions without adding unwanted Speed.
Duplicate Copies	Retain or allocate elsewhere	Prevents accidental tier awakening; saves resources for units with linear scaling.
Support Characters	Maximize ranks and survivability	Ensures buffers survive boss area-of-effect damage and act before Legion.

Team Building Around Baseline Legion

To maximize an unupgraded Legion, construct a party that accommodates high action volume and turn manipulation:

Use Multi-Turn Debuffs Over 1-Turn Buffs: Standard 1-turn stat buffs expire after a single action. Because Legion takes multiple Extra Actions in a single round, short-duration buffs fall off immediately. Prioritize supports that inflict multi-turn Defense Down, vulnerability, or poison directly on the boss, ensuring the debuff persists through all of Legion's consecutive strikes.
Deploy Persistent Aura Buffs: Passive, aura-based stat increases remain active regardless of how many individual turns Legion takes.
Include Action Gauge Batteries: Once an Extra Action sequence finishes, use turn-meter batteries to push Legion's gauge and restart her sequence before the enemy can retaliate.