Apart from this, Pokmon-EX play just like any other Pokmon card
Each one of them, especially in the right deck, can drastically change the outcome of a game
Vampiric Tutor is one of the best tutors in the game, Relentless Assault is one of the best extra combat phase cards, Necromancy is a good reanimation spell, and Natural Order is a great way to tutor a big Green monster directly to the battlefield
Sure, it might stretch the definition of what a Goblin is, but it has to qualify, as both sides of this card produce a Goblin creature, either in token form on the front or as a zero-mana-value enchantment creature on the backside
I mentioned this with Stoke the Flames above already, and the card demands a rather specific set of conditions to be good (enough cheap creatures and powerful enough instants/sorceries to be worth copying), Howls effect is actually quite busted if you can enable raid
Aim for a single-EX deck (so no Charizard-Moltres or Arceus-Dialga) and get the second copy as soon as possible to maximise the chances of getting one in the starting hand