This guide is about creating a base that is optimized for offense while being matched with a lower Town Hall during war.

So, as normal, I’ll look into the gameplay algorithms and mathematics and show how to optimize base creation.

Background Information

The war search algorithm is extensively discussed in an earlier post. However, it raises the question of how to maximize warfighting capability without being matched against crazy-hard opponents. The secret is to reduce your base’s war score while maximizing offensive capabilities.

According to SuperCell, players are primarily scored on their defenses. Having a lot of high-level defense upgrades results a higher score, therefore, harder war matchups.

SuperCell has not elaborated more details other than these vague statements. However, there are many interested players posting their findings on Reddit or the SuperCell forums. Some players have created identical bases and upgraded one item at a time to view how their rankings change. Using this method, the community has some heuristic understanding of how upgrades affect their war score and ranking. Combined with the knowledge provided by SuperCell, some approximate rules emerge:

1. Town Hall level does not contribute to war ranking. This information was provided directly from SuperCell.
2. Expensive defenses apparently contribute heavily to your war ranking. For example, a fully upgraded Tesla costs (cumulative) 11.25M gold. Teslas are thought to be the third most contributive element to one’s war ranking, surpassed only by Inferno Towers and X-Bows (in that order).
3. Walls have been shown to not (substantially) contribute to war ranking. This means you can max your wall levels without being matched to harder opponents.
4. Heros contribute to the war ranking by an unknown amount.
5. Traps contribute to the war ranking by an unknown amount. Since traps cost substantially less than fully upgraded weapons (i.e. Hidden Teslas), their contribution is probably far less than the major weapons.

Therefore, the war algorithm scores your base predominantly on the strength of your defensive buildings. High-level defensive structures such as the Inferno Tower or X-Bow disproportionally skew your score to stratospheric levels. If your clan has a few Inferno Towers, you’re likely to face high-level clans in war matchups. In short, the higher level your defenses, the harder the war matchup will be.

Theory

It is unknown how each weapon contributes to the war ranking – by counting the most recent upgrade cost or the cumulative cost (the summation of all the upgrades up to and including the current level). See the tabulation below for TH9 weapons. I added the Inferno Tower, although not available at TH9, as a comparison. Notice the Level 2 Xbow upgrade cost is 5M, which is less than the Level 7 Wizard Tower upgrade (5.36M). This would suggest the Wizard Tower upgrade contributes the most to a TH9’s war ranking.

Another way is looking at the cumulative cost. The Xbows cost a total of 8M gold. However, the cumulative cost of several other weapons exceeds that of the Xbow. This would suggest that Teslas (14.75M), Wizard Towers (12.54M), Air Defenses (8.48M), and Archer Towers (9.86M) all contribute more to a TH9’s war ranking.

The casual observation among players is when a TH9 builds an Xbow, their war ranking skyrockets. It’s not clear how Xbows compares to Wizard Towers or Teslas, because a truly quantitative analysis is extremely difficult. Two identical TH9 bases would need to co-exist, and have one each upgrade a Wizard Tower and an Xbow to see how their war rankings result.

However, it is very clear that high-level defenses result in high war rankings, resulting in tougher war matchmaking results. TH9 is when the big differentiation emerges, with most upgrades costing around 4-5M gold. TH8 players probably don’t need to worry about their upgrades affecting the clan’s overall war ranking.

Strategy

This strategy is totally backwards to how I’ve played the game thus far. I’ve always played very aggressively as a farmer to upgrade by base as quickly as possible. Little did I know that this would play against me for war matchups. As previously mentioned, your weapon levels aren’t a big factor until TH9, where the impact in war matchups become very noticeable, very suddenly.

1. Once you hit TH9, focus on upgrades that do not adversely affect war matchups. This means pour your gold into walls and elixir into army camps, barracks, and troop upgrades. You can build the new TH9 weapons (i.e. fourth Wizard Tower or Air Defense), but don’t upgrade them over TH8 levels. This keeps their upgrade costs under 3M gold. If you’re really nervous, don’t upgrade your Teslas beyond level 5 or 6.
2. Upgrade everything that does not contribute to war ranking – especially DE drills and storage. Build the fourth gold and elixir storages and upgrade any remaining mines and collectors.
3. Upgrade all bombs. These are especially useful against hog attacks and don’t contribute much to the war ranking.
4. Save your Dark Elixir for troop upgrades. If you have a huge surplus, consider occasional hero upgrades, but try to not progress beyond level 10 (This is still at TH8 level. The Barbarian King caps at level 10 for TH8.) I alternate between regular troop and dark troop upgrades to prevent stockpiling too much, and capping my heros at level 10.
5. Upgrade defenses only after your troops and walls are at maximum levels. Upgrade the defenses that matter the most first – e.g. Air Defenses or Wizard Towers. Since the consensus is the Xbow results in huge war ranking, save it for last.

I wish I would have known this before advancing to TH9. I would have done it differently. However, I will use this method when advancing to TH10.