The main plan in the plan was to kill Pain.
Pain was the leader of the Desert Cowboy Gang; he was the backbone of this notorious criminal force. No matter what the vengeance army did, if Pain was still alive, another Desert Cowboy Gang could rise any day.
This was why Tim prioritized killing him.
By bringing the whole Vengeance Army to attack and overwhelm the main base of the criminals, it would make sure that they had no time for reinforcements to come help them which would increase the chances of Pain being killed.
If Pain was killed would exterminating the Desert Cowboy Gang be realistic. If Pain was killed, they could finally go out there and exterminate all the other bases of the criminal gang one by one.
The Vengeance Army was superior in numbers to the criminals in the main base by more than 5 to 1, this was their greatest advantage.
