some more reasons this would take ages/be nearly impossible
Space station 13 is 2-d, blockland isn't.
health system (suff/tox/burn/brute)
chemistry system (unless we're talking about /tg/, but then, that's still pretty loving complicated).
thinkdos would be hard as balls to replicate, along with all the other computers.
bomb system
construction system
z-levels (unless we're gonna have one map with seamless transitions, but that would be pretty lame. if you've ever played ss13 before you know why.)
pods
NPCs
CLOTHING. Like seriously, clothing is half the game. How are you going to implement all those different clothing slots into blockland?
zero gravity, space wind, jetpacks and space suits.
blockland has a datablocks limit, you know. (unless there's some super secret haxor way to disable the limit that i don't know about.)
but mind you, i'm not completely against this idea. if someone actually pulled it off and pulled it off well, that would be pretty loving sweet.