Inverted World.
Erase.
The slime hurriedly expanded the connection, causing the slime underneath the ground to burst. This way, Theo wouldn't be able to erase it since he had to handle the burst first.
The eruption forced Theo to stop and move away to avoid getting covered by the slime. However, the slime wouldn't be able to make a reckless attack anymore. After all, he had identified the slime's weakness. One wrong move would cause a huge blow to the slime.
The slime became more and more annoyed by Theo's intelligence. He thought that it was impossible to persuade Theo. In fact, if Theo would ever be persuaded, he must be plotting something. He would be too dangerous to be kept alive.
Even if his life could be controlled if he were to be reborn with the slime body, Theo might be able to outsmart him.
That was why the slime had changed his approach toward Theo. There was no need to be good to Theo anymore. He had to be removed.