BUILDINGS
🚧
Gate — indestructible, allies pass, enemies blocked
🗼
Turret — auto-fires every 5s, 3sq range
⚡
Power Plant — 3× factory income + 30% speed boost adjacent
🚀
Artillery — fires every 2min, 20sq range
ULTRA EXPANSION
🧱
Wall L1 $500 (click→upgrade L2 +$500, L3 +$2k)
🗺
Wing $25k · Rear Land $50k (expands base)
♗
Bishop — auto anti-air, 4sq diagonal
♕
Queen — auto anti-air, 6sq all directions
🛡
Survival: waves every 2min · boss every 10th