hatsune miku mtg bonus card New is a $0.33 Dud Favorite Bonus Cards in Magic:

When youve got packs to open youll see the Packs icon in the upper left side lit up

As a cheap two mana value option, it can turn online fast

3 Dark Confidant Emet-Selch, Unsundered Esper Terra Gogo, Master of Mimicry Golbez, Crystal Collector Hope Estheim Joshua, Phoenix's Dominant Kefka, Court Mage Kefka, Ruler of Ruin Kuja, Genome Sorcerer Mysidian Elder Quistis Trepe Shantotto, Tactician Magician Summon: Esper Ramuh Tellah, Great Sage Terra, Magical Adept The Emperor of Palamecia The Lord Master of Hell Trance Kuja, Fate Defied Venat, Heart of Hydaelyn Vivi Ornitier Xande, Dark Mage

While other options like Geier Reach Sanitarium and Bonders Enclave are good too, War Room is probably the most universal and easy to activate