Li Wei, who was a little away from them, didn't hear their conversation and pondered about his summoning skill.
'My summoning skill is level 30, and to summon a rare monster, I have to instill more mana in the skill. When I summoned the wolf, I only used 250 mana, but if I used more mana, a more rare monster will be summoned.' he thought arranging the information in his mind.
With the summoning skill, he can only form a total of ten contracts, but he can also dissolve them and form a new one with another monster.
After getting contracted, he can also control their attributes, but he needs to make sure that his summoning skill level can do this; if it's low, he wouldn't be able to do it.
The summon can also be sent back to their worlds where they came from. Their world is more like a monster space from a game, where they will recover their MP and HP at a faster rate.