So, by the end of the game there are many characters whose fate are left unknown:
*Originally the Lilly from comics, but turned into just another Lilly because of the comics Lilly having a different backstory in Road to Woodbury.
*If left behind, the last we see of her is her running away from a zombie on the road.
*If brought along, the last we see of her is her getting away with the RV. Kenny later says that the RV won't be able to go farther than a 30 miles.
*If shot or left behind at Crawford, she runs to the nurses' office, never to be seen again.
*If saved, leaves the mansion right after Vernon and is never seen or heard from again.
The cancer survivors
*Steal the boat from Lee's group by either beating Kenny/Ben up, threatening to shoot Christa and Omid or by just taking it while everyone is out and leaving a note behind.
*Had to get the boat to the shore and seeing as the walkers quickly overrun the city, they either gave up on the boat and escaped the city on foot or got killed while taking the boat to the shoreline.
*Originally had an on-screen death, as mentioned by his VA in an interview with TWD wiki, but it was changed at the last minute.
*If he saves Christa, he is stuck in a room with walkers coming at him. If he kills Ben, he is left at an alley with zombies closing in at him. Either way, he is never said to have died in the end, just "lost" to the herd.
Christa and Omid
*They get separated from Lee near the Marsh house.
*They can be told to look for Clem by the train, to meet Lee and Clem at the hotel or to look for another boat ( I think ). Clem can be told to look for them at the last scene. No matter what, they are not seen at the epilogue.
So, what do you guys think happened to them and will we see them again in S2?