A tip or two for success; buy most of or all the "passive" upgrades. Then, max out Skeleton Archers, they have incredible range and are cheap to make. Next buy special units, and spend money on maxing them out too. If this is done, then put a little money into portal defense. On the battlefield, create one or two special units, (Berserk, Knight etc.) and then create as many Skeleton Archers as you can. Don't activate "Auto" movement; the consequence is your units run around and get themselves killed. With "Auto" off, your troops will stay in the general vicinity of your portal, and efficiently wipe out any or all soldiers coming your way. If done exactly as described, your portal will remain guarded and the opposing army will be reduced to body parts in no time. Works like a charm.
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