The Essential Last War Season 1 Week 2 Guide: Crimson Legion, Mason UR Promotion, and Serum Shop Timing

As soon as Week 2 begins, your first priority should be the Serum Shop. The shop refreshes every 7 days, so the best items are not just valuable, they are time-sensitive. If you delay too long, you risk entering the next reset with fragments spent poorly or not spent at all.

The best approach is to separate purchases into three tiers. Buy long-term power items first, secure the progression materials that keep your resistance and roster moving second, and only touch filler purchases if you are comfortably ahead on fragments.

The Crimson Legion launches coordinated attacks against alliance Cities twice during Week 2. The first attack starts Tuesday at 12:00 server time, usually against your weakest City first, and the second round follows on Friday.

The Legion reveals its target 12 hours before the battle begins. That announcement window is your alliance's chance to organize reinforcements, adjust rally leaders, and make sure the players with the best squads are prepared to absorb the hardest waves.

Each defense consists of 30 successive waves, with one wave arriving every minute for roughly 30 minutes. Up to 20 players can reinforce, and the difficulty climbs as the event progresses, so early complacency often leads to late collapse.

One of the biggest Week 2 mistakes is promoting Mason too early. Thursday is the optimal timing window because it aligns with VS Duel's Hero Training day and the Arms Race Hero phase, turning a normal upgrade into a major scoring spike for both alliance and personal rewards.

Before promotion, Mason must already be a 5-star SSR hero and you must own a Legendary Hero Badge. Just as important, make sure you have already spent your Skill Medals on him and invested in Mason's Wall of Honor before pressing the promotion button.

This matters because the promotion process includes a refund mechanic. You get back the fragments invested into the Wall of Honor as Mason shards, and you recover the Skill Medals you already used. The tradeoff is that Mason resets to a 3-star UR hero with skills back at Level 1, so his immediate power dips even though his long-term ceiling becomes far higher.

If your alliance is unsure whether it can hold a City against the Crimson Legion, use these power benchmarks as a rough planning tool. They are not perfect guarantees, but they give alliance leadership a practical baseline when assigning reinforcements and deciding whether a City is realistically defensible.

Week 2 is also full of smaller edges that strong players exploit while everyone else is focused only on the headline events. These details are where you turn good timing into efficient progression.

If you follow this Last War Season 1 Week 2 guide with discipline, your alliance should defend more cleanly, your Serum will go further, and Mason's promotion will create much more value than a random mid-week upgrade ever could.