ultra rare mega ex pokemon cards POKEMON~100 CARD LOT~GUARANTEED EX. EX. FULL ART HOLO OR SECRET RARE! : Toys & Games have for your premier collection. Pokemon - XY - Flashfire

Part 2 Ive recently picked up several of Shogakukans magazines published around the time of the contest in order to hopefully reveal additional information

For just 2 Fighting Energy, you can use Draconic Buster instead, which deals a huge 260 HP considering its cost, though you do have to discard all Energy from the card when using it

You may exile no more cards than are required to pay the spells cost You do not gain mana by exiling cards for Delve, you exile cards instead of spending mana from your mana pool

This might help increase the overall play of these types of cards but it won't help Thoughtseize who remains kind of the pile