Echoed Voice deals damage starting at base power 40, and increases by 40 each turn if used by any Pokémon on the field, up to a maximum base power of 200.

It does not reset if it misses, as long as the move is attempted each turn. The power does not increase during a turn (if multiple Pokémon use it), only after each turn.

When a Pokémon is holding Normalium Z and uses its Z-Power, Echoed Voice turns into Breakneck Blitz and has base power 100.