Farming refers to the runs (also called “rounds”) you do with your tower where you are focused on Coins and Cells gains (as opposed to Milestones runs and Tournament runs). You can resume a run a maximum of 25 times.
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Overall, to improve your farming, you may want to see the various strategy guides: Guides & Strategies.
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Starting out with the game you are likely to farm following a Turtle Strategy (early game), and thereafter transition to a Blender Strategy (early game). And thereafter you may consider Orb Devo Guide for Increased Coin Gain & Progression, Orbless (such as The FreeUp Orbless Strategy, and eventually Glass Cannon Strategies [WIP].
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See especially the farming-related tips and FAQs below: 💡 Farming-Related Tips and ⁉️ Farming-Related FAQs.
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And to overall enhance your farming, you are advised to check out Guide to Improving Coin Income, and to consider using an emulator, if you can (Guide to Using Emulators (play the game on PC/Mac)).
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