Mecharashi Rainbow ST Upgrade Priority Guide

To optimize your roster in Mecharashi, focus your limited Rainbow upgrade materials on high-impact ST (Standard Type) units that serve as core damage dealers or essential utility anchors. Units such as Hasteraze and Rosa represent top-tier options due to their ability to manipulate the battlefield, break parts efficiently, and sustain damage output. Before committing rare upgrade currency, ensure the targeted mechs directly complement the pilots you have already built.

Rainbow Upgrade Criteria and Priorities

Because Rainbow materials are scarce, investments must deliver long-term value across multi-stage activities like Alliance Trials and Armed Conquest. Evaluate your roster using the following priority structure:

Priority Level	Unit Focus	Key Attributes & Mechanics	Ideal Deployment
Priority 1	Core Damage Dealers	Multiplicative damage bonuses, multi-attack triggers	Alliance Trials, Armed Conquest
Priority 2	Utility Anchors	Movement speed buffs, armor piercing, debuff removal	General & Escalating Content
Priority 3	Synergy Specialists	Enables specific turn loops or pilot combos	Niche Tactical Battles

When assigning upgrade materials:

Match ST weapon slots and passive abilities directly to your primary pilots' skills.
Select mechs that retain usefulness across multiple modes rather than single-encounter specialists.
Prioritize units that provide unconditional movement or defense-bypassing utility.

Avoid spending scarce resources immediately on new banner arrivals. Free-to-play and low-spending players should wait for community testing to verify whether an ST unit requires expensive accessory investments or specific high-rarity pilots to function effectively.

To maintain progression efficiency:

Save pulling currency for mechs that introduce distinct mechanics rather than minor stat upgrades.
Hold a reserve of Rainbow materials to react quickly when balance updates or new pilot synergies shift the meta.
Observe successful high-level loadouts in the Combat Simulator before altering your upgraded squad configuration.