Tonight's show is a bill of rare Kill Rock Stars reunions for a good cause (to help former KRS employee Natalie Cox pay for treatment of a rare form of cancer). Headlining is powerhouse drums-and-guitar duo the Need, who from 1996 to 2001 floored audiences with the combination of Radio Sloan's jarring metal riffs and Rachel Carns's thunderous upright drumming and raw yet operatic vocals. Rounding out the bill are garage-rock trio Bangs, lovable hesher nerds C Average, and one-man brown-sound generator Thrones. Tonight is one of only two shows this summer with the Need and Bangs; don't miss it. (Crocodile, 2200 Second Ave, www.thecrocodile.com. 8 pm, $12, 21+.)