A sketch of one of the mystical animal species from my setting
These creatures are called guurs. This one, in particular, is an Orion-type guur connected to the energy associated with the hypostasis of the Orion constellation

Guurs have magical crystals and plants grafted into their bodies (for example, in this drawing the horn is made of crystal). They are very territorial animals, but they are not aggressive as long as you do not harm the nature within their territory

When a guur dies naturally, it transforms into a huge tree that infuses the surrounding area with energy, helping to fertilize the soil and support life around it

However, if a guur is killed, it explodes. Its corpse, attempting to regenerate, instead drains energy and life from everything nearby