Avaliable for free at https://www.bay12games.com/dwarves/ or as a paid premium version on Steam or Itch.io
>What is the difference? Both are the same game on the same version (51.xx). The free version uses ASCII as a tileset (but you can mod other usermade tilesets and graphic packs) With the premium version you pay for a premium tileset + premium OST + access to beta branches and steam integration (if on steam).
>What is next? Fort mode siege mechanics changes, rework and general spice up is the next update. Hatches and doors no longer stop invaders, and constructed walls vulnerable comfirmed so far End of Lua beta and merge into the main branch
>What has changed since I last stopped playing X years ago Check the version history on the wiki https://dwarffortresswiki.org/index.php/Version_history
Dwarf Fortress has an extensive wiki which can help you with your question about DF as well as providing info about modding and 3rd party tools: https://dwarffortresswiki.org/Main_Page https://dwarffortresswiki.org/Utilities
>A bunch of guides to various parts of fort-based living: http://imgur.com/a/nGyRF
Strike the earth!>We're working on siege features for the time being. I started with a first stab at siege planning - forbidden hatches and doors no longer stop invaders, and constructed walls are now vulnerable as well (as promised, you can opt-out.) Next up I'll continue tackling the siege items from the dev page. This will include stronger constructions and other defenses, and more varied invaders. More info as I go!