When you fire upon an enemy in Child of Eden, you're not beating, killing, or defeating it. You're "purifying" it. It sounds like a flouncy semantic sop for Tetsuya Mizuguchi's abstract rail shooter - shooting is shooting, right? But the distinction is important. Every hit creates, rather than destroys, piling visual and audial building blocks onto a scene that's part video-game, part music synthesiser. Darting moths transform into fluttering butterflies; flowers bloom, scattering seeds that burst into lush foliage, the music building towards a thrilling crescendo the more the level becomes populated with colour. That you bring life, rather than death, to the world is the difference that makes Child of Eden so exhilarating, emotive and empowering.