FOSS gamedev and creative worlds

ello i am working on making a mod that automaticly decays things very slowly and u can fix it with duct tape
but that is just my problem
i need help to figure out how to fix things and make them decay slowly
can anyone help

to make a node decay:
you must have 2 types of node, one with good condition texture & the other with bad condition texture.
both nodes will have a metadata variable "age" with some value.

make an abm that decreases "age" over time. When the "age" of good node reaches 0 then it will be replaced with the bad node. When the "age" of bad node reaches 0 then it's destroyed.

thank u but i also need the code to fix things