How to Upgrade Lower-Tier Troops in Last War

To upgrade lower-tier troops in Last War, open any idle Barracks, select your target higher tier, and tap the promotion arrow icon next to your lower-tier soldier reserves. Promoting units upgrades them directly to your highest unlocked tier instead of training new recruits from scratch, consuming only a fraction of the standard training time and resource cost while preventing weak units from filling your Drill Grounds.

Steps to Promote Soldiers in the Barracks

Troop upgrading uses the built-in promotion feature in the Barracks interface rather than standard recruitment:

1. Select an idle Barracks: Tap any Barracks building inside your base that is not currently training units.
2. Find the promotion icon: On the troop training screen, locate the upward-pointing arrow icon displayed next to your lower-tier unit inventory.
3. Choose the starting tier: Select the specific lower-tier soldier group you want to elevate. The screen shows the total count currently stationed in your base.
4. Set the batch quantity: Adjust the slider to determine how many soldiers to upgrade. The menu displays the required Food, Iron, Gold, and total completion time for that batch.
5. Confirm the upgrade: Tap the confirmation button to start the promotion timer. Once finished, those selected units become your designated higher-tier soldiers.

Repeat this cycle across your remaining Barracks until your reserve roster matches your current tier milestone.

Resource and Time Differences: Promotion vs. Training

Promoting an existing soldier costs significantly less than training a new recruit because the game credits the resources and time already spent on that unit.

Upgrading soldiers one tier below your current maximum completes rapidly. Promoting units across multiple tier gaps takes longer per batch, but it still requires far fewer resources and minutes than recruiting an equivalent number of fresh troops.

Converting older units also solves roster congestion. Automated squad replenishment draws from your Drill Grounds to fill march formations. Keeping weak tiers in reserve risks deploying under-leveled units into your active squads during combat, defense, or alliance rallies.

Using Troop Promotions for Event Points

Troop promotion is one of the fastest methods to earn points during competitive training events, including daily Arms Race troop training stages and Alliance Duel (VS) Day 5. These events grant points based on the tier your soldiers reach upon completing training.

To maximize points during these windows:

• Stockpile lower tiers early: Train lower-tier units during off-peak periods when speedup boosts are inactive, or leave existing low-tier reserves untouched until event day.
• Spend speedups on promotions: When the event begins, apply training speedups exclusively to promotion queues. Because promotion timers are shorter than fresh recruitment cycles, each speedup item yields finished high-tier units and event points much faster.
• Stack active buffs: Coordinate with your alliance to ensure alliance-wide training boosts and relevant minister titles are active before initiating large promotion batches to reduce overall speedup consumption.