Marina Bay got the known MRT lines:
North South Line (Marina Bay / Marina Pier as terminus. Marina
Barrage extension is possible as well) ---- Opening in 2014 for
Pier
Circle Line (Marina Bay Extension, Bayfront, Marina Bay
terminus) --- 2012
Thomson Line (Possibly Marina Pier or Bay and Marina Barrage)
--- 2018
Eastern Region Line (Probably Marina Barrage) --- 2020
Oh, wait, Downtown Line! --- 2013 (Downtown station,
Bayfront)
In short, NSL, CCL, DTL, TSL, ERL with:
Marina Bay, Bayfront, Downtown, Marina Pier, Marina Barrage and
1 more station (Possibly Marina East, for Eastern Region Line)
??