This system of prioritization is known as 'aggro' (aggression), and mastering it is the most critical mechanical skill in the game.
If you cannot reliably predict which target an enemy unit will choose to attack, you are relying entirely on luck.
How Units See the Arena
Every single unit in the game possesses a hidden 'sight range' value, usually measured in invisible tiles.
Understanding exactly how many tiles a unit can 'see' allows you to place distractions at the absolute maximum possible distance.
Use the arena tiles as a visual guide.Resetting aggro saves games.Adjust your placements for air threats.
The Geometry of Defense
Large tanks have massive hitboxes, meaning melee defenders can attack them from slightly further away than smaller troops.
The physical mass of the tank will actually push the Miner backward, forcing him to lose range on the tower and retarget onto the tank.
AI LogicTactical ApplicationDistance RulePlace a cheap skeleton exactly one tile closer to the enemy than your fragile ranged attackerVision RefreshThe tower will rescan and target the swarm
Practice Makes Perfect
Reading about aggro ranges is completely different from actually executing pixel-perfect placements in the heat of a live match.
Once you internalize the invisible grid that governs the AI, the game slows down dramatically.
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