"Those fools!" said Lord Quixote (A fine joke isn't it!), "They should know it's impossible to take the castle from this side of the mountains!"
"But sire their army is huge!" said the court scribe, "Surely we are doomed."
"Oh no, scribe," explained Quixote, "it matters not how big their army is, it's totally impossible to reach the keep from that side of the mountains, and if they use archers and siege equipment our crossbows and ballistae will take care of them easily. No, they'll definitely not be victorious this day."
"Well I feel much better," sighed the scribe, although his doubts were still not totally quashed.
In the distance a horn sounded, the siege had begun!
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Don't worry it isn't as hard as it sounds, like all true siege maps it's definitely not impossible. :-D