Doom 3 BFG edition includes DOOM,DOOM 2,DOOM 3,DOOM 3 Resurrection of evil + The lost missions. This is really cool and cheap pack!
Cool game, new textures, new graphics but old levels and mechanic. I recommend this game who want to recall old doom 3 gameplay and levels. Rather interesting, not hard. Also you can find here full walktrough : https://www.youtube.com/playlist?list=PL8mew_CQr9JIisZy2jl8pX4haCOS-MYQn

And here full walktrough Doom 3 Resurrection of evil (BFG EDIT) https://www.youtube.com/playlist?list=PL8mew_CQr9JL_X3v7CwUUBqIeXSUSW8fU

Full Walktrough Doom 3 The Lost Mission (BFG EDIT) https://www.youtube.com/playlist?list=PL8mew_CQr9JJ9pcVE7hqrWloer5vNXXlZ