If two or more attacking fleets arrive at a star during the same tick, I understand that the largest fleet starts losing ships first. Once one attacking fleet is destroyed, does the combat effectively start again or does it carry on contiguously?

Eg: Defender has 10 ships. Weapons level 2.
Two attacking fleets of 5 ships each. Weapons level 1.

Algorithm A:
First fleet gets reduced to 2. Defender reduced to 9.
First fleet reduced to 0 AND second fleet reduced to 4. Defender reduced to 8.
Second fleet reduced to 1. Defender reduced to 7.
Second fleet reduced to 0.

Algorithm B:
First fleet gets reduced to 2. Defender reduced to 9.
First fleet reduced to 0
Second fleet reduced to 2. Defender reduced to 8.
Second fleet reduced to 0.

Jay will need to confirm, but I believe it is still the sum total of all carriers+star ships that is used in one single calculation per star, not multiple calculations. … unless there are multiple players (more than 2) arriving at the same tick, then who knows?

I am pretty sure it carries over the remaining to the next fleet. So if your weapons level was 15, and fleet A had only 10, then 5 would be taken from fleet B. The defender kills their total number, then the attacker, regardless of how many fleets are in orbit or attacking. The first carrier will be destroyed. You can’t send 2 weaker fleets with a combined total needed to win, without losing one of the actual carriers. I learned that early on from experience.

Three and four way battles go in rounds. A attacks B, B attack C, C attacks D, D attacks A. Only the actual defender gets a bonus in those types of battles.

For example, if I send a fleet of 50 ships will it have the same result as 2 fleets of 25? My gut tells me the 2 fleets will take more casualties. Is there a way to calculate this?

Lets say Weapons 5 both sides, 40 defending ships, 50 attacking ships. Battle calc says attacker wins with 2 ships.

If we have two attacking fleets of 25, would it work if I calculate 40 vs. 25 = 20 defenders remaining. Then 20 vs 25 = 1 attacker left?

Jay adjusted the combat algorithm around 2015 MAR.

@AnnanFay gave an explanation of how Jay’s code works.

So in your combat examples :

case 1
defender has 40 ships garrison & weapons 5 +1
attacker has 1 carrier of 50 ships & weapons 5
attacker wins with 2 ships = 1 carrier + 1 ship

case 2
defender has 40 ships garrison & weapons 5 +1
attacker has 2 carriers of 25 ships on each carrier & weapons 5
combined combat
attacker wins with 2 ships = 2 empty carriers

Because damage is distributed ( evenly ) proportionally across carriers & garrisons.
attacker loses 48/50 ships = 96% loss
96% loss applied against 1 carrier of 25 ships is loss of 24 ships.
Repeat again for all subsequent carriers or garrisons.
Jay’s code continues loss distributions over each fleet until each one of all 48 ships are killed.
Any individual ships that think they could have any hope of sneaking by Jay’s percentages are mercilessly hunted down and disposed of in Jay’s digital disintegrator.
None escape their fate !
He is very meticulous that way !! MUHA HA HA !

case 3
first combat
defender has 40 ships garrison & weapons 5 +1
attacker has 1 carrier of 25 ships & weapons 5
defender wins with 20 ships

second combat
defender has 20 ships garrison & weapons 5 +1
attacker has 1 carrier of 25 ships & weapons 5
attacker wins with 1 empty carrier