The Gameslayer was a new video gaming console appearing in the novel Eagle Strike.
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It was a new game system belonging to Damian Cray, about to be launched by Cray Software Technology at start of Alex Rider's Eagle Strike mission. The black-suited ninja character that is the symbol of the Gameslayer system is called Omni, whose features change to an exact double of the gamer when the console is used; when Alex plays the Feathered Serpent game, Omni looks just like him.
Alex was allowed to be the first in the world to play on the Gameslayer, testing the Feathered Serpent game at the Gameslayer launches press conference.