HollowOne is a fast graveyard-fueled aggro deck relying on Vengevine, Detective's Phoenix, and cheap Hollow One casts, so cheap interaction and graveyard disruption are key. Unholy Heat is excellent here since our own deck fills its graveyard with various card types including artifacts via Mishra's Bauble, Grinding Station, and mill effects, making Delirium easy to enable for the 6-damage mode that kills anything they have. A second Tormod's Crypt helps proactively strip their graveyard to slow down Vengevine returns, Detective's Phoenix bestow, and Faithless Looting recursion. Fire Magic's Fira mode for {2}{R} deals 2 damage to each creature, enough to kill their many 1-toughness and 2-toughness creatures like Blazing Rootwalla, Marauding Mako, and Hardened Academic. Boomerang Basics is too slow and tempo-negative against their fast clock, while Haywire Mite cannot target their artifact or enchantment creatures (only noncreature ones) and Endurance's graveyard disruption is less impactful than direct removal against this creature-heavy aggro list.