This system of prioritization is known as 'aggro' (aggression), and mastering it is the most critical mechanical skill in the game.
Top-tier players use their deep understanding of aggro mechanics to lead enemy armies on wild goose chases around the map.
Vision and Targeting
When a unit is deployed or finishes destroying a target, it scans its specific sight range for the closest valid enemy.
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.You must use a stun spell (like Zap) to force it to rescan.They ignore the river and take direct diagonal lines.
Manipulating the Z-Axis and Hitboxes
You can use the physical bulk of your own units to literally push enemy troops out of their preferred path.
This highly advanced technique, known as 'body blocking', requires absolute precision but can save hundreds of tower hitpoints.
AI LogicTactical ApplicationProximity PriorityPlace 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
You must spend hours in friendly battles practicing these specific interactions until they become pure muscle memory.
Once you internalize the invisible grid that governs the AI, the game slows down dramatically.
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