Quick Answer
Guildrun SS difficulty is a difficulty tier, not a separate mode. It sits after S and before SSS in the difficulty ladder. The material says SS punishes weak frontlines faster, makes slow scaling riskier, and forces better economy and challenge choices.
What Changes at SS
At SS, you can no longer rely on a shaky tank and hope the carry fixes everything. The frontline must survive long enough for the team to cast, trigger, or scale. If the tank dies early, the rest of the comp usually has no time to do its job.
Slow scaling also becomes riskier. Stall, Shard generation, and permanent growth can still work, but only if the comp survives the early pressure. If a build needs too many turns before it matters, SS can punish it before the payoff arrives.
Recommended Team Structure
Use a durable frontline, a real damage carry, and support that directly improves the core. The support should add survival, Rush, Shield, Frost, Poison, Crit, Shards, or another effect your board already uses. Random support that does not match the plan is usually too expensive.
Economy matters more on SS. Wide teams can become costly, and the material warns that challenge fights can pressure your resources. Buy power that solves the next problem instead of buying every interesting unit.
Challenge Fight Risk
Challenge fights can be valuable, but SS makes bad challenge selection more dangerous. If the reward does not immediately strengthen your plan or solve a known weakness, passing can be safer. The Red Rift material has a similar lesson: sometimes the next fight matters more than a greedy long-term idea.
Do not claim SS is easy. The current official balance material says sub-SSS strategy diversity exists, but that does not mean careless comps win. SS is the place where beginner habits start breaking.
SS vs SSS
SS prepares you for SSS by making you respect positioning, economy, and frontline quality. SSS and Endless demand even stronger scaling and cleaner engines. If you can beat SS consistently, the next step is to study best comps, Endless scaling, and patch notes.