From Encyclopedia Awesomica
The summon skill is a unique skill – it is the only one you gain access to by means other than being a certain class or by unlocking it. The summon skill becomes available to a player after they have successfully cast bind on a monster.
Once a monster is bound, the caster gains access to the summon skill, which he/she can use to bring the bound creature into other duels. The cost to summon each monster is based on the combat rating of the monster. A monster can only be summoned into one duel at a time. If a monster is summoned in one duel and a user starts another one before that one is finished, the monster will not show up in the list of available skills.
Bound monsters are managed similar to skills. Once a player has bound a monster, he/she acquires access to a new page called “Summon Management”. This page can be accessed through the drop down menu on any page of their profile.
Bound Monsters are equipped by default, but if you want to unequip them, simply click the red E next to the appropriate monster. Unequipping monsters will make them no longer appear in your skill drop down list so it can be smaller and less cluttered if you desire. Once unequipped, that E will instead be a zero with a line through it – click on that symbol to equip it again. There is no cost to do this and it can be done as many times as you desire.
Bound monsters can be made stronger through training. To train a monster, click on the icon of the stat you want the monster to train in. Once selected, that icon will up to the far right and the price of that training will display. Training a monster will increase the amount of the stat by 1% each day. Training is reset each day and must be reselected. Use the bar of icons at the top of the list of monsters