FOSS gamedev and creative worlds

I'm just wondering what everyone's favourite building tools are?
Here are my favs, and a few extras I've seen which look useful, but I haven't needed yet...

Worldedit (with my player controlled alignment and test-loading code, which unfortunately hasn't been pulled into the master), since this dramatically improves loading schematics and is great for (eg) building walls and repeated structures.
https://github.com/dgm3333/Minetest-WorldEdit

Unified_Inventory - well of course you need a decent inventory.
https://forum.minetest.net/viewtopic.php?f=11&t=3933

Bridge Tool - for building bridges and staircase floating in mid-air
https://github.com/Kilarin/minetest-mod-bridgetool

Display All Installed Nodes - for providing a showcase of each node
https://forum.minetest.net/viewtopic.php?f=9&t=11294

Wrench - haven't really used this, as I disliked screwdriver and had already written my own, but this does more than mine.
https://forum.minetest.net/viewtopic.php?f=11&t=11162

Replacer - exchange/replace nodes with one click, again I haven't really used this one yet, but like the idea
https://forum.minetest.net/viewtopic.php?f=11&t=4676

Mini Sun - a bright light source for building in dark places
https://forum.minetest.net/viewtopic.php?f=9&t=6222

Fireballs - I use this for blasting holes and have recoded it slightly to provide a zone-replace tool
https://forum.minetest.net/viewtopic.php?f=11&t=6154

Growwall - ease the pain of creating long walls, and import maps/walls from a bmp image
https://forum.minetest.net/viewtopic.php?f=9&t=11565




BTW it isn't meant to be a showcase of my code, just I tend to know what tools I needed for particular jobs, and quite like writing my own...