This lets you get those cards that you would want specifically
This card was very relevant when it came out because it allowed you to target planeswalker cards at a time when planeswalkers were a huge threat
The game starts with a deck of 60 cards with different Pokemon characters

Bant Delirium | Shadows Over Innistrad Standard | Roman Fusco Creatures (16) 1 Bruna, the Fading Light 1 Gisela, the Broken Blade 1 Ishkanah, Grafwidow 1 Linvala, the Preserver 1 Ulamog, the Ceaseless Hunger 3 Tireless Tracker 4 Primal Druid 4 Thraben Inspector Instants (4) 1 Immolating Glare 3 Dissenter's Deliverance Sorceries (14) 1 Descend upon the Sinful 2 Nissa's Renewal 3 Fumigate 4 Spring // Mind 4 Traverse the Ulvenwald Enchantments (5) 1 Quarantine Field 4 Cast Out Lands (21) 6 Forest 2 Island 3 Plains 1 Irrigated Farmland 1 Lumbering Falls 2 Evolving Wilds 2 Scattered Groves 4 Fortified Village Sideboard (9) 3 Negate 1 Essence Scatter 2 Gideon, Ally of Zendikar 2 Declaration in Stone 1 Cataclysmic Gearhulk By hitting Delirium with creatures that acted mainly as chump blockers (Thraben Inspector and Primal Druid) and Spring // Mind (two card types) I was able to get insane value against various midrange creature strategies with Delirium cards like Descend Upon the Sinful and using Traverse the Ulvenwald for major threats like Gisela, the Broken Blade, and Bruna, the Fading Light

With a pair of colors well suited to ramping mana, putting Emiel at the helm can allow you to build an amazingly resilient deck, as seen on an episode of Game Knights
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