Liam did some hard training in the cave.

[i]Diglett, the Mole Pokemon,Lives about one yard underground where it feeds on plant roots. It sometimes appears above ground. Its skin is very thin. If it is exposed to light, its blood heats up, causing it to grow weak.

Dugtrio, the Mole Pokemon and the evolved form of Diglett. In battle, it digs through the ground and strikes the unsuspecting foe from an unexpected direction.They are extremely powerful, and they can dig through even the hardest ground to a depth of over 60 miles.[/i]

After training Liam returned to the Pokemon Center to heal up.