With the bomb in the core, Ryan decided it was best to just completely destroy Rapture. Obviously. Not only that, but when I found him, he made me kill him. Very odd.
Then… a big fat spoiler. Which makes the next bit somewhat hard to mention, really. I got out of Ryan’s office, and met up with Tenenbaum and all the Little Sisters. More revelations occurred, and it now seems that Fontaine (who isn’t dead after all) is the guy to go after.
I made it to Olympus Heights, killed Cohen (who decided he loved me and wanted me dead as a result – freak) in his apartment, found a formula which has made all my plasmids go nuts, and now I’m off to find some more of it. Of course!
Also managed a few more achievements today, including maxing out all my tonic tracks and some more research, as well as some normal story-progression ones.