Cyanta
when I saw that it was updated, I started having a fit of laughter (abnormal laughter more like hysteria than laughter)
The reason why Artoria can only have Excalibur as a weapon is because she is still technically alive, so only weapons that are immediately at hand could be available for her as a servant. Since this Artoria is truly a summoned spirit of the dead it wouldn't be unreasonable to also have in her possession: Caliburn; Carwennan (dagger with Presence Concealment properties); Clarent (ceremonial sword stolen by Mordred); Prydwen (shield/surfing board, also stolen by Mordred)