Ultimate offering is a fantastic card when you have a deck full of level 5-6 monsters. You can use it to inflict a great amount of damage to your opponent. This is how it works: have 1 to 3 monsters on the field. If you duel right, your opponent should have 1 or 2 monsters in face-down defense position on the field. first, during your battle phase, destroy the opponents monsters as far as possible. Watch out for Effect monster cards and trap/magic cards. Always attack with the monster with the highest defense so that effect monster cards will target that monster. If you can't attack anymore, don't end your battle phase but use Ultimate Offering (you do have to have enough LP left, never use thi when you are around 2000) it doesn't matter that the monsters on the field are stronger than the monsters in your hand, but do summon weaker monsters when you're planning this. Summon as many monsters as possible and attack the opponents LP. if there are more monsters in your hand, keep going. That way you can keep summoning monsters for a low price (that's my opinion) and get the opponents LP way down.