When enabled (gloopblocks_lava_damage = true in minetest.conf), lava
will "bake" or "burn" neighboring nodes, turning them into other things.
Affected volume is 3x3x3 around any given lava node. Nodes only
transform from one thing to another, they do not actually catch fire
(unless the game's fire mod does it).
For example, sand will turn to either obsidian glass or moreblocks coal
glass (to imply that it was a dirty process), sandstone will turn into a
sandstone block, cobble into its respective stone, trees or wood into
coal block, etc. Some things will just burn to ash straight away,
others may take two or three stages before hitting their final form.
Also items with "plantlike" draw type within the affected volume will
simply disappear after a time (as if totally incinerated).
Supported mods include cottages, castles, bakedclay, and a few more.
Third-party mods can add support for lava damage by either adding
entries in the form of `["oldnode"]="newnode"` to the
`gloopblocks.lava_damage_nodes` table, or by adding
`["somegroup"]="newnode"` to the `gloopblocks.lava_damage_nodes table`
(the latter wants only a group name, without any "group:" prefix).
Though I haven't tested it, it should be possible to overwrite existing
entries in either table, but I highly discourage this, unless absolutely
necessary.
VanessaE