KH: Bestial Summons

Here Hiccup explains what Bestial summons are and how they work (a ot of technical crap etc.) But basically if you save up magic/mana points you can Bestial summons once Hiccup shows you how. When this happens, he summons toothless with a Dark Bestial Summons and Toothless is seriously powerful so he kicks butt.

The beasts you summon level up like you do, but you have to use them a lot to get that to do so. In other words they don't level up with you, it s separate. They do specific attacks, but some of the Fallen CAN ONLY BE KILLED by using a Bestial summons. So it's a handy trait and tends to lean the game to needing Sora to choose Magic over sword or shield in the beginning.

If the Beast you summon runs out of HP you lose some too, but not nearly enough to make it count significantly.
Note that Hiccup does not summon Toothless a lot while he is in your party.

Hiccup/Jack: (C) Dreamworks
Kingdom Hearts: (C) Squeenix
Art: (C) ME