If there are any supply players could have asked for on the battlefield, most of them would asked for the Double Damage boost!
The boost works by increasing the muzzle velocity of any type of projectile by multiple folds, allowing players to get that extra damage boost for their tank. It's the ultimate boost for the offensive player, giving them the opportunity to deal twice as much damage before having their tanks turned into a pile of charred chassis.
It is also incredibly useful in 1-on-1 tank fights when both players are equally skilled. In fact, during such fights, any tiny advantage would help tremendously and tip the scales to the side with the extra advantage.
Similar to any type of supplies, you can order a crate of "double damage" goodness from the in-game shop using diamonds and deploy it in the battle arena. Naturally, you would want to pick a suitable location to deploy the drop box lest your teammate, or worst, your opponent, gets to it first.