You do have to discard an Energy after attacking, but Fire decks have no shortage of acceleration options to make that cost manageable
I found it on the playground after a rainy day- short to say this card is TRASHED
3 Blazing Bomb Chaos, the Endless Clive, Ifrit's Dominant Cloud, Planet's Champion Esper Terra Firion, Wild Rose Warrior Freya Crescent Garland, Knight of Cornelia Gilgamesh, Master-at-Arms Giott, King of the Dwarves Gladiolus Amicitia Hill Gigas Ifrit, Warden of Inferno Item Shopkeep Joshua, Phoenix's Dominant Kefka, Court Mage Kefka, Ruler of Ruin Kuja, Genome Sorcerer Lightning, Army of One Lightning, Security Sergeant Mysidian Elder Phoenix, Warden of Fire Prompto Argentum Queen Brahne Raubahn, Bull of Ala Mhigo Rydia, Summoner of Mist Sabotender Sandworm Seifer Almasy Shantotto, Tactician Magician Summon: Brynhildr Summon: Esper Ramuh Summon: G.F
This has neither value or power or even utility
If one of those creatures can't attack its owner that turn due to a spell or ability (such as Chronomantic Escape), you may have it attack another player, attack a planeswalker an opponent controls, attack a battle an opponent protects, or not attack at all
It helped clear up a corner case issue about knowing the commanders exactly location in the library