Talk:FGO 2016 Summer Event/@comment-122.55.57.66-20160817100337/@comment-28048698-20160817215737

Remember something: technically each different manifestation of an Heroic Spirit is different to the other ones. Cu Chulainn Caster is different to Cu Chulainn Prototype and Cu Chulainn FSN (and, of course, to Cu Chulainn Alter). Each manifestation summong one part of their legend, or one part of how they are seen in their legend. One good example of this is Gilles de Rais. When he is Saber, it's the part of his legend where he was a loyal knight. When he is Caster, it's the part of his legend where he is mad and evil, sacrificing people and all that.

Servants like the ones that are from halloween, summer, christmas, etc aren't serious Servants so I doubt their personality have a logic explanation. However... well, we can say they can have a different personality because they are a different manifestation. Maybe this childish Mordred is one that doesn't have Artoria like she usually do, or where Artoria accepted her as her child, etc.