A simple analytical theory about minimalist tower defense: forward containment theory
This model aims to establish a tower fire protection guide with certain reference significance.
Here are some concepts:
Frontal fire: Fire that damages the enemy at the front
Side firepower: a side attack on the enemy group that "eats the passing soldiers" from the side
Front: The most accessible position on the road that the enemy can reach
So based on the above settings, we can easily draw a very basic conclusion: "When the frontal firepower is strong enough, the frontline will retreat; when the firepower is insufficient, the frontline will move forward and the game will fail."
Therefore, "controlling the front line" is a key element in tower defense games.
The reason why the front line advances is that the frontal firepower is too late to destroy the following enemies, then we can get the formula
The minimum frontal firepower required to control the front line = (enemy HP - side firepower) × enemy movement speed
Okay, given the above premise, let's imagine what would happen on a strictly guarded road.
1. Promotion period
In the early stage, when the enemy has just entered the road, there is no side firepower, so the demand for frontal firepower is high and usually cannot be met. At this time, the front line will advance.
2. Control period
As the front advances, the enemy's flanks are exposed within the range of our defense towers, and as the front advances, the flank firepower becomes stronger and stronger. At this time, the need for frontal firepower is reduced and can usually be controlled at this time. The front line will not advance at this time.
An ideal defense usually stops at this stage.
3. Backward period
If the player increases firepower in a timely manner, the enemy will be destroyed faster than the enemy can replenish it, and the front line will retreat.