The prompt was followed by a drop-down list of all the organs inside Adrian's body. However, as Adrian went through the list, he realised there wasn't anything he could replace at the moment.
Adrian wondered if there was another way to increase the number of organs he could use. The system didn't fail to respond, but Adrian did not like the response.
[Upgrade the
"You got to be kidding me!" Adrian couldn't hold back and opened his mouth, a mistake he immediately regretted as seawater flooded his mouth, choking him.
He immediately swam to the surface to get rid of the salty water in his mouth and coughed to his heart's content before diving into the sea once again.
Once back inside, Adrian checked the upgrade requirements for [Monster Codex]. Thankfully, it was simple enough as he only needed to fight and register different kinds of monsters in the codex.