Pros:
* High ATK and DEF stats
* Can protect your monsters from destruction or removal effects
* Can be summoned quickly with cards like Sphinx Teleport or Pot of Extravagance
* Can be used to search for other Sphinx monsters in your deck
Cons:
* Can be vulnerable to cards that target face-up monsters or monsters with high ATK
* Can be difficult to summon without specific support cards
* Requires two tributes, which can be a constraint
Overall, Theinen the Great Sphinx can be a powerful and versatile card, but it is important to use it strategically to get the most out of its effects.