Cards such as Monster Reborn only revive any of the Gods for 1 turn, and to summon them, you have to sack 3 creatures (their star level equals 10!). Trap and Magic cards do not affect them, and Equip cards also only affect them for one turn. Osiris and Ra are Dragons for their types, but Obelisk is a Warrior-Type.
God of Obelisk's attack AND defense points equal 4000! For it's ability, which happens to be the best ability in the game... If you sack 2 monsters on the field, you can inflict 4000 points of damage directly to your opponent's life points, and along with that, destroy every monster on your opponent's field (In the cartoon, this attack is called the God Hand Crusher).
God of Osiris's attack and defense points are X000 (X is the number of cards in your hand, SO, if you have 3 cards in your hand, Osiris's attack and defense is 3000). When your opponent plays a monster face up, it's attack and defense is decreased by X000 (1000 times the number of cards in your hand at the time... so when they play a monster in attack mode and you have 5 cards in your hand, that monster's attack points are decreased by 5000). Same goes for it's defense points (if that monster has less than the number of decreased points, that monster's points is just 0, and is not destroyed). You CANNOT use Sangan or Witch of the Black Forest to get Osiris from your deck.(in the cartoon, this ability is Thunder Force and Summon Light Impact).
God of Ra's attack and Defense are equal to ??? or commonly as X. In order to get an attack and defense for this God, you must first play the card. When you play it, you must sack 3 monsters to summon it. If you add those sacked mosnter's attack and defense points, it equals Ra's (for example, if you sack 3 monsters and their attack points are 3000, 1800, and 500, then Ra's attack points are 5300! Same goes with the defense). If you special summon Ra, then it's attack and defense equal 0, but is not destroyed. You can attack the same turn you summoned Ra as well. If you pay 1000 of your life points, you can destroy any creature on the field. It's final attack, which is called God Breath Cannot - Called as such in the cartoon, allows you to pay all your life points, except for 1, and add it to Ra's attack points. Since it can attack as soon as it is summoned, this is called a One Turn Kill.
Some of the above translations could be mistaken, but for the most part, they are correct.
