Few facts are known about his face. Yet, all theories stated that Guertena is either a middle-aged or old man. On the recent version of Ib, a portrait of him is displayed, yet his face isn't shown. Therefore concluding that Guertena is still a mystery to all.
Very little is known about Guertena, though it seems he was a skilled and passionate artist having an entire museum for just his work alone. In fact, his work was so good that some of it came to life, implying he may have some magic in his background. This does not appear to have pleased him, as in A Paintings Demise it's implied he keeps a close eye on the main characters and will kill them if they leave without meeting the appropriate requirements.
Gathering tons of ideas from the game, here's a list of fanmade theories.
- Garry is Guertena. Though this theory is just a thought, people gave this attention as they try to realize the idea.
- Guertena painted Mary as a memory for his daughter or his 'dream' daughter. A lot of theories stated that he based on his painting, 'The Lady in Red'. Due to this theory, fans also lead to this theory. Though, this theory was less believed when Mary mentioned that The Lady in Red was her 'sister' in the newest version of Ib.
- Guertena had a past relationship with Ib. Any child with a huge imagination could enter the gallery. Why Ib? The thought came to people, trying to connect the paintings and Guertena, one by one.
- Something's wrong with Guertena himself. Despite the fact that his paintings are constantly praised, it was theorized that he had extreme emotions while painting his art. This lead to the solution on why the paintings were moving.
However if you start the game and walk around the gallery there is a lady wearing black (Or blackish blue) near the sculpture [Fusion] (Or ??? if your starting fresh. It's the blue almost melting sculpture on the second floor at the bottom right corner; between "Taste-Cleansing Tree" and "Your Dark Figure.") She will sadly mention that Guertena is in fact dead but if he was still alive she would have loved to have been his apprentice.
- 'Theories' - http://ibtheories.tumblr.com/