Creatures can use their energy to craft different objects. It is activated by arranging XP cards in a certain pattern.
That can be energy barriers, support for plants, own body modification, ~clothing, different signs.
The quality of the objects and the way they look like is defined by what energy it was crafted from.
Different objects require different amounts of energy. So the bigger is the energy capacity, the more type of objects can creature make.
There should be commands for crafting specific objects. Commands are learned from creatures, and the mastered commands form creature skills.