This is Natsu fighting with his fire dragon roar.  Which is very powerful.  He also has a very strond friend/rival which is very strong and uses ice magic.  His name is Gray.  He also has Laxus as rivals.  He is also a dragon slayer so he can eat fire, and was trained by a dragon.

This is Gray, he uses ice magic and is part of the guild fairy tail.  He can make this with his ice magic.  Like weapons, for example, an arrow, a cannon, etc.  Gray and Natsu are both scared of erza because she is a extremely powerful wizard which can crush both of them.

This is erza, her magic is able to transform different armor and weapons out of thin air.  She is a S class wizard for a reason.  She is also one of the most powerful wizard in fairy tail.  She is another rival of Natsu.  But she can beat him pretty easilly.

This is lucy who can summon celestial spirits with keys, that is her magic.  Her spirits fight using different types of magic.  Most are also really powerful, some can research and much more.

This is Laxus who uses lighting magic.  He is the second most powerful wizard in fariy tail.  He is another rival of Natsu.  But he can beat Natsu with a single punch.

Makarov is the third master of fairy tail.  He uses light magic and the giants wrath.  He is the third most powerful wizard in fairy tail.  His magic can let him turn as big as a giant.

This is Gildarts, he can explode things.  He is the most powerful wizard in fairy tail.  His power surpasses everyone in fairy tail.  He can knock you off your feat without even touching you or attacking you.