In literature, Jorge Luis Borges' Library of Babel is an imagined space where all the books and all the possible books are stacked on shelves in an endless library. The Library's infinite corridors are better realized in ECHO, set on a dormant planet where each interior is a part of an impossibly large Victorian palace. As En, you find yourself sneaking, running, and shooting your way through an army of clones that learn and adapt from your every action. The mechanics cleverly force you out of your comfort zone, living as an improvisational survivalist. Do I shoot and let my clones learn how to aim? Or do I sneak silently, hoping I can avoid them better than they can avoid me? ECHO, on all fronts, felt refreshing.