When a EB levels up, their strongest stat gets an extra 3 points, though their lowest stat ether only goes up by 1, or doesn't go up at all. 

When an EB matures, they are able to understand all that they hear. Though if they want to speak them as well, they have to study like everyone else.

An EB who has mastered their elements can make any attackers regret hitting their bodies. Physical attacks on Wind, Fire, Water, or Earth EBs cause the attacker to take 1-4 points of damage times the damage dealt to the EB. Magical Attacks on a Magic EB lets them use the spells they were hit with until the battle phase is over.