What Happens When You Betray an Alliance?

Break an alliance first and you are marked a traitor for 30 seconds. During that window everyone attacking you takes half the usual losses and advances 20% faster.

Thirty seconds sounds short. It is more than enough for a border to collapse, and Nations preferentially target traitors.

The numbers

Item	Value
Traitor duration	30 seconds (300 ticks)
Attacker losses against you	×0.5
Attacker advance speed against you	×0.8 (faster)
Alliance duration	5 minutes

A “10 minute” alliance duration circulates in some writeups. The source says 300 * 10 ticks at 100 ms per tick — 5 minutes. Lobbies can override it with a custom setting, but the default is five.

Half losses matters more than it sounds. As covered in attack ratio, an attacker’s loss multiplier bottoms out at 0.6 no matter how many troops they commit — the traitor debuff is the only thing that punches below that floor.

Who gets marked

The player who breaks the alliance first. The check reads:

On breaking an alliance, if the other player is not already a traitor and is not disconnected, mark the breaker.

That gives you two exploitable exceptions.

1. Breaking with an existing traitor is free. If someone has betrayed a third party and is still inside their 30-second window, you can break your alliance with them at no cost to yourself.

2. Breaking with a disconnected player is free. No reason to stay tied to someone who left.

The in-game control panel actually tells you both of these when they apply.

Alliances expire on their own in 5 minutes

This is the crux of the decision. Alliances lapse automatically, and a lapsed alliance is not a betrayal.

If you can wait 30 seconds, wait. If you can wait 5 minutes, definitely wait.

If the alliance is close to expiring there is no reason to eat the traitor mark. Watch the timer and strike right after it lapses — penalty zero.

When betraying is still worth it

Situation	Call
You can fully encircle them	Do it. Encirclement costs zero troops and transfers their gold
They are about to be eaten by someone else	Better you than them
They are your only land border	Nobody else can punish you for 30 seconds
Their troops are all committed elsewhere	This window may not come again
Surrounded by enemies, behind on troops	Don’t. You will not survive 30 seconds
Lots of Tribes nearby	Don’t. Bots prioritize traitors

Not getting betrayed

• Track the expiry time. Your ally is running the same math. Just before it lapses is the dangerous moment
• Keep some troops on the allied border. An empty border raises the expected value of betraying you
• Watch for an ally whose territory could wrap around yours — encirclement costs them nothing
• One defense post on a chokepoint ruins the economics of betraying you

Related — attacking stops trade

Separately from the traitor mark, trade with anyone you exchange attacks with is suspended for 5 minutes. If you have built an economy on ports, that loss can exceed whatever you gain by betraying.

Choosing your fights is your economy. See Where Should You Build Ports?.

More

• What Attack Ratio Should You Use? — how much to commit after breaking
• Combat Math — encirclement and the other modifiers
• Defense Post Range and Placement — minimum insurance