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School transmutation [sonic]; Level alchemist 4, bard 4, druid 4, sorcerer/wizard 5
Casting Time 1 standard action
Duration 10 minutes/level
You can perceive the world by creating high-pitched noises and listening to their echoes. This gives you blindsight to a range of 40 feet. The echo-producing noises are too high-pitched to be heard by most creatures, and can only be detected by dragons, other creatures with this ability (such as bats), and creatures with hearing-based blindsense or blindsight. You cannot use this ability if you are deaf, and cannot detect anything in an area of silence.