It's better than that. It gives you a damage buff to any weapon that you fire at Atheon. Some say up to 5x damage (it's a wiki article, so don't know how accurate). It's active for 30 seconds after you kill the last oracle in Mars/Venus. It also recharges your super faster. In other words, when you are going through Mars/Venus - HURRY. While people are killing the oracles, the relic holder needs to go to the gate. They kill the last oracle and run to the gate. Just before they go through, he heals them (don't even stop walking). Through the gate and into the middle to kill Atheon.