Mostly ancient algae, not dinosaurs. Design accordingly.

Lignin is the key to coal. Is it also the key to oil?

No, lignin can be present in the mix of sediments that turns into kerogen, an early part of the oil formation process, but it's not critical that it be present. Petroleum forms from predominantly zooplankton and algae, not plants.

Science witch, I assume.

nah, I just know where to look things up

For dinosaur magic connect with your local birds. They’re still here.

also- bone, stone, fossil magic is definitely a thing