Battle stats are what determine your Dragon's reliability on achieving Gold-Tier depending on its overall performance (dependant on its Nº of Shots, Base Damage, Titan Damage Boost and Hidden Stats), and durability against damage. These stats divide in two types:
Visible Stats: Information that's visible in-game which include:
Nº of Shots: Determines the amount of shots a Dragon has in total;
Base Damage: Determines the general damage of a Dragon's single shot;
Titan Damage Boost: Determines how much the Titan boosts its Damage;
Battle Health: Determines how much can your Dragon endure against ship damage, this is also one of the two stats that increase with the Titan stage.
Hidden Stats: Information that's hidden from the player, these stats are often considered as the most important stats in Battle Events - all these stats are hidden within a file in the game's Assets. These include:
Fire Range: Determines how long can your Dragon stay at a safe distance while keeping in-target of the ship. The game uses Unity Unit which often uses the Meter unit though the developers could've potentially used Foot Unit instead, so 1 Unity Unit = 1 Foot;
Critical Hit Chance: Determines the probability of getting a Critical Hit, a Critical Hit doublesd the Base Damage;
Cooldown: Determine how long an individual shot takes to reload;
Recharge: Determines how long the total of shots takes to reload.
Regarding the removal of Firepower, please check this section.
↑* (Localed In Hidden Stats) - Instead of calculating the average or median, because the Stat in question uses the Unity Unit or Meters to calculate the distance of a Dragon's range, it's best to calculate the mid-range of said Stats to indicate what's the extreme-medium of all the distances. In this case, the mid-range was found by multiplying 25 (lowest range) with 78 (longest range) and dividing it by 2 (25*78/2).