Richard the Lionheart's death in 1199 was attributed to a crossbow bolt in his shoulder near the neck which became gangrenous when his surgeon 'carelessly mangled' the operation. Personally, I'm not a big fan of Richard and reckon there's no recovering from such a wound, but what might have happened if he had survived? Would he ever have children with Berengaria of Navarre? If not, might his nephew Arthur succeed him instead of John? If he limps on until the date of John's OTL death in 1216, what of the Magna Carta?