His first attack, Second Bite, requires one Dark energy and two colorless energy. It deals 40 base damage, but does 10 more damage for each damage counter on your opponent’s Active Pokemon. This can make Krookodile’s first attack quite deadly if you’re dealing with an already wounded foe.
Megaton Fang costs 2 Dark energy and 2 colorless energy for 130 base damage, which is slightly above average. However, it does require you to discard a card as additional cost to attack, making the little bit of extra damage a bit more costly.
While he’s not exactly a highly competitive EX Pokemon card, Krookodile EX is fairly powerful and could find some Modified play at some point if the right deck emerges for it. Otherwise, it’s just a really cool card to have as part of the collection, as it only has the one printing.