Some cards have both a short name and a subtitle. For all purposes, including rules and deckbuilding, such a card’s name is “[Short Name], [Subtitle]”. Example: Kai’Sa, Evolutionary and Kai’Sa, Survivor both have the short name Kai’Sa, but they have different names. You can include 3 of each in your deck under normal deckbuilding rules. If one of them is your Chosen Champion, the other is not.
§ 132.4 Core Rules PDF (officieel)
§ 132 Name
