It seems much of the issue with oracles is spun around Atheon's fight specifically too. The oracles before and during the Templar fight are pretty straightforward when you know the locations and the ads aren't too problematic (unless you're taking to long to kill the Templar of course). Atheon, on the other hand, seems a little too close for comfort even when you're experienced since oracles don't give you a whole lot of time to react and the outside team already has to deal with Supplicants mixed with Harpies.