Spoilers for terapagos lore
Terapagos is a Pokémon that was burried deep underground and crystallized. So what did it look like before. I present Normapagos, the Ancestor Turtle Pokemon. They used to be a common species found all over the world. They were normal type and were very defensive but slow pokemon. They were very resilient and had the ability to enter a dormant state when times were tough. Seismic activity hit what would become Paldea and a few Normapagos were buried deep within the fissures that formed, most meeting their end but a few went dormant. As the ecosystem changed, the Normapagos gradually evolved into the ancestors of turtle pokemon we know today and the Normapagos species gradually went extinct. But those who were burried and dormant were still there, but gradually dying off as they could only remain dormant for so long. One Normapagos survived longer than the rest and being under so much pressure, crystallized. Then a meteor struck the earth above it,creating the great crater of paldea. The Normapagos absorbed the energy from the meteor, becoming the legendary Pokémon Terapagos and giving birth to the terastrastion phenomenon.
by Wabuup