Crypt Rats requires a significant mana investment to wipe anything tough off the board, but it does an excellent job of clearing out 1/1 Elf Warrior tokens and 1/1 Bird Illusions from Murmuring Mystic
You gain control of that creature if it regenerates this way
Add Cybernetic Overflow and you can use Core to bait an opponent into an attack only to destroy that monster (and, if you have enough CDs in the hand, field or grave, clear their board completely)
The 1400 attack power that was supposed to be added to the Red Demons by the power-up connector was instead added to Weizel Ein, becoming 3200, and the Red Demons' attack power was reduced to 0
just know that, if you do want to get the Mega Venusaur ex into your collection, it doesnt have to be too expensive unless you want the rarest version of the card
One is simply to increase their effectiveness through buff effects