Stark subbed, Arryn played. King's Landing and Rosby are under siege, Joffrey's fleet has been defeated and his faction dies next turn. If Tyrell (or any other faction gifts him a settlement) that is an abuse of the game mechanics and shouldn't be allowed unless they fund his army themselves and there is no debt. If we are talking about it in realism terms, it is completely unrealistic, no soldier would fight for a dying faction anyway and especially not for free.
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