Fertilizer Bot

Fertilizes the soil with animal waste.

Fertilizes crop tiles within 16 tiles of its station, one fertilizer each: crops on the tile grow 25% faster for an hour. It fertilizes 12 tiles (up to 48 with upgrades) per charge, empty ones too. Fertilizer comes from animal waste, collected by Waste Bots.

Recharging takes 16 seconds at its station and costs biofuel: 1, plus 1 for each capacity upgrade and for every second speed upgrade. Each upgrade costs more than the last, counted across all bots of its kind. Demolishing one takes its upgrades back off that count, so the next upgrade costs less.