Map making for source engine games

• Valve Developer wiki: https://developer.valvesoftware.com/wiki/Mapping_Sites & https://www.interlopers.net/ (a ton of HL2 content, but majority is applicable for other games too)
• There are also communities for other Source games, like http://tf2maps.net/
• Also there is a good tutorial series on making a TF2 map: https://invidious.weblibre.org/watch?v=fdpTT2pqIVY&list=PL2KT0JL74Qff_c1WbqNi4K5yAmpWAUQlq&index=1
• ... for making a CS:GO level: https://invidious.weblibre.org/watch?v=dhcoHQcrYKA&list=PLfwtcDG7LpxF7-uH_P9La76dgCMC_lfk3&index=1 & https://invidious.weblibre.org/watch?v=pMGnPu8NdK0&list=PL-454Fe3dQH0WCzAsmydsr24NFaFrNC_h&index=1

Map making for Halo: Custom Edition

• Install Halo: Custom Edition: http://hce.halomaps.org/index.cfm?fid=410
• Install HEK (Halo Editing Kit): http://hce.halomaps.org/index.cfm?fid=411
• Download a tag pack (for map editing. you also need HEK): http://hce.halomaps.org/index.cfm?fid=6690 and/or https://haloce3.com/downloads/tags/misc-tags/complete-halo-pc-tagset/
• Install the newest patch (removes CD check, etc.): http://hce.halomaps.org/index.cfm?fid=6798
• Blam Script reference: http://www.modacity.net/docs/bslbible/

Where to get maps/tags?
http://hce.halomaps.org/
https://haloce3.com/ce/
To play a Single Player map, open console and type: map_name my_map

Level/mod making for Skyrim

• https://en.uesp.net/wiki/Skyrim_Mod:Creation_Kit
• https://www.creationkit.com/index.php?title=Main_Page
• https://loot.github.io/
• https://github.com/TES5Edit/TES5Edit
• Lore: https://www.imperial-library.info/

Where to get mods??
https://www.nexusmods.com/skyrimspecialedition/
https://www.afkmods.com/
https://tesalliance.org/forums/
https://www.fliggerty.com

Making a level for Doom
Doom is the easiest game to start with. You want to install SLADE and Doom Builder 2 or Ultimate Doom Builder. Use ZenNode for building nodes. I recommend making a Boom map first.

• Install GZDoom and/or PrBoom+. If you use PrBoom+, you need to install sdl2_mixer and fluidsynth + soundfont-fluid packages before you build/install the PrBoom+ package.
  (Otherwise the sound won't work or it is ear rape.)
• https://doomwiki.org/wiki/File_formats & https://zdoom.org/wiki/Main_Page & https://wiki.zandronum.com/Main_Page
• https://www.realm667.com/index.php/en/
• Watch these first: https://archive.org/details/doom-level-design-chubzdoomer_202005-500202 → https://invidious.snopyta.org/watch?v=6arDCzmhONY&list=PL-36gm0W-VKmfVVCGe1HTVABepUXshxjY&index=4
• https://www.doomworld.com/forum/topic/74073-vanilla-level-editing-lesson-1-preliminary-reconnaissance/ + http://cd.textfiles.com/instantdoom

Where to get WADs from?
https://www.doomworld.com/idgames/
https://www.wad-archive.com/
https://www.gamers.org/
https://www.moddb.com/games/doom-ii
https://forum.zdoom.org/

>Is it possible to make half life 2 maps without buying half life 2?

No, because nowadays Hammer is distributed with the game (IIRC, "runhammer.bat" in the game folder). BUT you could map for CS:GO or TF2 (which are free).