Energy Blue has many efficient energy-creating cards like Aether Meltdown and Glimmer of Genius
The only trick worth mentioning is that the ability to discard a card is often an upside because we can use it to get a land or creature (the two hardest card types for our deck to get for delirium) in the graveyard to start milling away our opponent's deck with Manic Scribe
The most common variety are cards which increase the cost of opposing spells (Trinisphere, Thorn of Amethyst, Grand Arbiter Augustin IV), but some punish actions with the loss of life or other resources (Painful Quandry, Manabarbs), limit access to lands and mana (Winter Orb, Opposition), or outright stop opponents casting spells (Drannith Magistrate, Ethersworn Canonist, Rule of Law)
These decks will often not even be trying to win a game outright as the first objective, but instead just want to show off the themes within
Speaking of which
In many ways, Pokmon ex are simply updated versions of Pokmon V , being stronger than average cards which reward two Prize Cards when Knocked Out, although evolved Pokmon species are treated as such instead of all Pokmon ex being Basic Pokmon
