Ravana's honestly not that bad. I've had a ~75%ish success rate when DFing it alone when I'm bored. Usually failure only comes from people quitting too quickly. It's pretty easy normally, but becomes super easy with echo if the party is bad enough to wipe a bunch of times to build it up.
The last thing I did before logging off today actually was DF Ravana EX. We only wiped once, and that was because a healer was new.
Most failures I've had with Bismarck were because of one or both of the following reasons:
-Dumb tank(s) who can't read
-Extremely low DPS (~400-ish with echo) that my own DPS output can't compensate for
In the absence of those two factors, it's almost always a success (eventually).
