[quote=@Heat]
[@TheRedViper] While making the Arryn CS I had the idea of having the House try to get the clans to come under their rule. Maybe they'd consider uniting if the Vale was under attack by a powerful force or something.
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I think it would be cool to see someone like, for example, a disgraced knight in service to House Arryn, see his chance for revenge by uniting the clans (however that comes about, may be a tad difficult) and leading them against House Arryn. An angry, ambitious knight in charge of 5,000 or-so clansmen would be a really useful tool for anyone trying to attack the Vale. If someone were to supply and fund the clansmen they would be a real nuisance for the Vale, either drawing them out to be attacked or keeping them pinned in. Not particularly relevant, just thinking out loud.