Thomas the Tank...Raven?!?! Azarath Metreon Choo Choo!
The blind bags are not only coded (Raven is number 61) but you can also see through them pretty well by moving the train inside up to the white part of the package. So the guesswork is pretty easy to work around on these things.
Some DC characters have been released in multi-packs, but I think the blind bagged versions can only be found in the blind bag series and aren't duplicated in the multi-packs (and vise versa). Blind bags are $1.50 each which is a fine deal for the size and for what you get here. Go get some!