Defense Speed
Overview
Defense Speed is a Hero Stat that determines a Tower's attacks rate, a Trap's rearming time, and an Aura's effect rate. Each Defense has a base rate that is converted into Times per Second and then augmented based on the Hero's Defense Speed stat. Unlike Defense Power and Defense Health, Defense Speed is applied as a percentage increase to a Defense's base rate instead of a direct coefficient to the stat.
Formula
The way that the game calculates a Defense's attack rate, rearm time, and effect rate is directed by the following formula:
APS(attacks per second) = bDS(Defense's base attacks per second) * ( 1 + ( DS (Defense Speed) - 250 ) / 300 )
Which is basically saying that every 300 points of Defense Speed you have over 250 increases your Defense's attacks per second by 100% of the base value
Example: Flameburst Tower has a Base attack rate of 2.5 seconds, or 0.4 Attacks per Second. At 250 DS the Flameburst Tower will be at that base value of 0.4 APS. At 550 DS the Flameburst Tower will be at 0.8 APS. At 850 DS the Flameburst Tower will be at 1.2 APS, etc.
Base Attack Rates
The Base Attack Rate of a Damage Type Defense does not change with the upgrade tier of the Defense (Changed in Foundation Patch 1).
Defense | Attack Rate | Attacks Per Second |
Cannonball Tower | 2.32 seconds | 0.431 |
Ballista | 4.84 seconds | 0.207 |
Flameburst Tower | 2.5 seconds | 0.4 |
Earthshatter Tower | 5 seconds | 0.2 |
Lightning Aura | 1.25 seconds | 0.8 |
Sky Guard Tower | 2.5 seconds | 0.4 |
Explosive Trap | 2.5 seconds | 0.4 |
Geyser Trap | 8.31 seconds | 0.12 |
Blaze Balloon | 12.2 seconds | 0.082 |
Poison Dart Tower | 3.33 seconds | 0.3 |
Defenses Unaffected by Defense Speed
The Poison Tick rate of the Poison Dart Tower and the Burn Tick Rate of the Blaze Balloon are not affected by the Defense Speed stat.