This unique defense map requires you to fend off hordes of enemy units using invisible scarab-launching sentries. Use your shuttle to plant whichever sentry you want and it'll automatically shoot when the level starts. Don't put all your sentries in one spot for two reasons; (1) the recharge time on the sentries is too slow and the enemies will take some hits and walk past. (2) all the scarabs will attack a single target, resulting in the other units unscathed. Good luck!