Finally, add "Kickfire" for a counter every turn (at least). Within 8 turns (including your opponents), and without even having to attack, this will equal 8000 points of damage. (This won't work if you include "Sacred Phoenix of Nephthys" in the combo, however, as it's effect will destroy "Kickfire".)
After Special Summoning this card, activate "The Seal of Orichalcos" to destroy it. During your next Standby Phase, it will Special Summon itself, destroying all monsters on the field in the process, leaving you with a 3200 ATK monster to attack directly with.
Use this card with "Safe Zone". This will make "Garunix" invincible, and even if "Safe Zone" is destroyed, the destruction effect of "Garunix" will activate.
If this card's Normal Summon is negated and destroyed through "Solemn Judgment", "Solemn Warning" or similar cards, then you can still revive it and destroy all other monsters on the field at the next Standby Phase.
When this card has been destroyed and sent to the graveyard, its effect will activate in the next Standby Phase, but only "Solemn Warning" can be activated against it (not "Solemn Judgment"); only negating and not destroying this card, because it is already in the graveyard, thus rendering it unable to get its effect to Special Summon itself again in the next Standby Phase.
Tip for against this card
If "The End of Anubis" is on the field, "Fire King High Avatar Garunix" will be unable to Special Summon itself from the Graveyard.