Terrakion is very good. Its amazing consistency can make it a dangerous deck to play against at a tourney. Problem? Energies. Terrakion may be all handy dandy with 2 energies by T2, but if Straight Terrakion cannot draw into enough or any EXP Shares, they are done. Eels can actually beat Terrakion, and mine has (Except my Eels is Zekeels w/ hydreigon so I spread with the Hydra and KO with zeks.). It is not BDIF, even with and added Terrakion EX, but It will become increasingly better because Terrakion has the same damage output as a regular terrakion, but attaches fighting energies to your terrakions as well. That will increase the decks potential a lot. Not to mention that Terrakion EX can strike for 50 (100 against weakness I think, may be wrong) T2, easily Koing weak basics that cannot reveng kill it.