Hi Lehnihon, thank you ^^
There isn't a fixed colour palette for the whole collection. Due to the large number of packs in the collection covering very different locations and atmospheres, I create colour palettes from scratch for each asset pack.
It is a design choice. Minifantasy's super low resolution sets a very defined framework, with its associated limitations. To counterbalance this, I give myself total freedom to create colour palettes for the packs, which allows me to increase the detail in the assets despite the restricted resolution.