The documented origin of explosives is from ancient goblin civilization's research into alchemy formulas and is currently one of the most important branches in the modern field of mechanical alchemy.
However, for the mages from the divine realm, these things indeed pose a bit of a challenge.
The gods of the divine realm, in order to keep the faith pure, have completely eradicated any existence of different civilizations' cultures.
It is something completely beyond the mages' comprehension.
There are no magic fluctuations, no process of energy converging, the installation is convenient, and once the powder ignites and the chemical reaction starts, the process of energy release is utterly irreversible.
Moreover, the reaction speed is incredibly fast, tens or even hundreds of times quicker than the release of similarly powerful magic.
In dealing with positional warfare, explosives indeed have an unparalleled advantage.