The Math Behind DPS in Be The Final Boss: Cost, Attack Speed and Population Slot Efficiency

In Be The Final Boss, army building often tempts players to chase the highest visible rarity or the biggest single-hit attack number. However, because castle space is strictly constrained by your army population cap, evaluating units solely by their raw Attack (ATK) creates severe economic and tactical inefficiencies.

To build a truly optimized castle defense, you need to understand the relationship between base attack, attack speed (SPD), population slot Cost, and mutation multipliers. Here is the mathematical framework behind true damage output and unit efficiency.

The Core Formulas: From Flat ATK to Effective Slot Output

Every unit in Be The Final Boss carries three core variables that dictate their actual baseline performance in combat:

• Base Attack (ATK): The flat physical or magical damage inflicted per swing or projectile.
• Attack Speed (SPD): The frequency of attacks per second.
• Population Cost (Cost): The number of army slots consumed when deployed onto the field.

Because total army size is capped by your skill tree's Population nodes, a unit occupying two slots must deliver twice the performance of a one-slot minion to justify its deployment.

Base DPS = ATK × SPD

DPS per Slot = Base DPS / Cost

Verified Unit Performance Comparison

Using Level 1 base un-mutated values verified in the repository combat ledger, here is how tracked units stack up when normalized by population slot efficiency:

| Unit | Rarity | Cost | Base ATK | Base SPD | Raw DPS | DPS per Slot | Altar Cost (Souls) | | --- | --- | --- | --- | --- | --- | --- | --- | | Deathlock | Epic | 3 | 210 | 2.0 | 420 | 140.0 | 100 | | Demon Butcher | Rare | 3 | 175 | 1.4 | 245 | 81.7 | 25 | | Tomb Hound | Uncommon | 2 | 100 | 1.2 | 120 | 60.0 | 5 | | Skull King | Secret | 4 | 150 | 1.5 | 225 | 56.3 | Unknown | | Imp Bomber | Rare | 2 | 100 | 1.0 | 100 | 50.0 | 25 | | Necromancer | Rare | 2 | 75 | 1.0 | 75 | 37.5 | 25 | | Bone Guard | Uncommon | 2 | 20 | 1.0 | 20 | 10.0 | 5 |

Key Takeaway:

Notice that Deathlock delivers 140 DPS per slot, whereas Skull King (despite holding prestigious Secret rarity) outputs 56.3 DPS per slot at Level 1 base values. Skull King compensates with massive health reserves and survivability, but players seeking pure wave-clearing damage will deplete their population budget if they replace dedicated damage dealers with multi-slot heavy units without calculating slot returns.

The Impact of Mutation Multipliers

Mutations introduce massive scaling that fundamentally alters the efficiency equation. When a unit rolls a mutation at the Summon Altar, the multiplier scales both Attack and Health, but leaves attack speed, abilities, and deployment Cost unchanged:

• Shiny Mutation: ×1.3 ATK & HP (+30% boost)
• Cursed Mutation: ×2.0 ATK & HP (+100% boost)
• Demonic Mutation: ×2.5 ATK & HP (+150% boost)

Because the deployment cost remains constant, mutations multiply DPS per slot directly:

Mutated DPS per Slot = Base DPS per Slot × Mutation Multiplier

The "Mutation Trumps Rarity" Theorem

A common dilemma is whether to deploy an unmutated Epic/Secret unit or keep a lower-rarity minion with a Cursed or Demonic mutation. Consider this direct mathematical comparison:

• Base Demon Butcher (Rare, Cost 3): 245 DPS \rightarrow 81.7 DPS / slot
• Demonic Tomb Hound (Uncommon, Cost 2): 120 × 2.5 = 300 DPS 150.0 DPS / slot

A Demonic Tomb Hound provides nearly double the damage density per castle slot compared to a clean Demon Butcher, while costing 80% fewer Souls to summon from the Altar. Never sacrifice a Demonic mutation simply to field an unmutated higher-tier unit unless the higher unit fulfills a mandatory crowd-control or damage-absorption role.

The Soul-to-DPS Conversion Ratio

When spending Souls at the Summon Altar, each rarity tier increases the Soul cost exponentially:

• Uncommon summons: 1 to 5 Souls
• Rare summons: 25 Souls
• Epic summons: 100 Souls
• Legendary / Secret: 500+ Souls (or low percentage chance)

During the early and mid-game, rolling for Demonic or Cursed variants of low-cost Uncommon and Rare units yields exponentially higher immediate damage per Soul invested.

The optimal strategy is to stockpile Souls until the Cursed Moon map event occurs (which doubles total mutation roll probability for 5 minutes), then roll aggressively on the mid-tier Altar. Rolling outside the Cursed Moon window burns valuable Souls on unmutated base cards that struggle past Wave 50.

The Golden Ratio: Balacing Frontline Tanks with Sustained DPS

Damage density is meaningless if your units cannot survive long enough to cycle their attack timers. Based on hero wave mechanics, the ideal army composition balances durability and damage under a 60:40 Rule:

1. 60% Population allocated to DPS Density: High DPS/Slot units placed within point-blank range of the enemy spawn gate.
2. 40% Population allocated to Dedicated Durability: High HP-per-slot meatshields (such as Bone Guard, Iron Skeleton, or Demonic Barbarian) positioned a fraction of a stud ahead of your DPS line to intercept the initial hero burst.

By anchoring your squad building in cold mathematical efficiency rather than rarity aesthetics, you will advance through boss rotations with minimal economic friction.