Please, note that Victory comes with some preparation.

Before the Town Defense starts, you need to prepare supplies because the possible maximum amount available during the Defense event will be the amount you managed to accumulate beforehand.

Once you get a special icon in the upper-left corner indicating that Zombies are close to the Town, it's time to accumulate supplies to defent the Town (please, note that the Town defense doesn't start before you accumulate enough supplies);

This can be done via: 

• Producing items;
• Initiating Supply Runs;
• Investing in building.

Once the minimal amount of supplies is reached and the Town Defense starts there are options to either start defense manually or perform an autobattle.