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.
Vision and Targeting
If multiple enemies are within that radius, the AI will almost always lock onto the absolute closest target mathematically.

If a massive, slow-moving tank is lumbering toward your tower, you do not need to place your defense directly in front of it.
They are easier to distract with cannons or teslas.Place distractions closer to them.Timing must be faster against fast troops. Manipulating the Z-Axis and Hitboxes
One of the most complex aspects of aggro management involves understanding the physical size, or 'hitbox', of different units.

For example, if an enemy Miner is locked onto your tower, you can deploy a large tank directly on top of him.
AI LogicTactical ApplicationDistance RulePlace a cheap skeleton exactly one tile closer to the enemy than your fragile ranged attackerAggro Reset on StunThe tower will rescan and target the swarm Mastering the Grid
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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