Only as complex as you want to make it! My very first Pokemon game was a case statement where you picked your first Pokemon and it emulated the dialogue.
My second attempt was before I knew about OOP or FP, and just had a C++ array that held Pokemon data in set indexes. That was during my first programming class haha
I do recall writing a text "battle" game in the Pokemon style with Harry Potter characters but that was a single battle sequence. It was also before I knew OOP and for my first programming class :) Your comment brought back some memories.
