Easy with +30wave/double HP/double amouts/double armor monsters, all in one strategy guide: put ALL of your attacking unit near the exit or the entrance of the map, to make all damage CROSS FIRE, simply put more totems/standards/posts to cover your attacking unit, while playing, just upgrade units, build more units and structures, and upgrade, that's it. Remember to make more supplyment of your gold, better more than 2 barracks and trading posts. Hit Plus if this is useful.
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