If you are not in a hurry, waiting often saves $3060 on the top three cards
There are plenty of incredibly powerful monsters that have effects protecting them from destruction
BT3-050 R Digimon Lv.4 Stingmon Color Green Cost 6 DP 5000 Digivolve Cost 1 Green 1 from Lv.3 Form Champion Attribute Free Type Insectoid Card Text 2 [Inherited Effect] [Your Turn][Once Per Turn] When this Digimon deletes an opponent's Digimon in battle and survives, gain 1 memory
While the green one is far and away the most versatile and easy to find a use for, none of them are unplayable, and all can slot into your mana bases without much trouble, especially given they enter untapped
The life is just gravy, though, and any green deck is going to jam this interaction because its just so premium
Hmm, thats a lot of lifegain you have there, James