Whenever an opponent attacks another one of your opponents, you and the attacking player each draw a card and lose 1 life
For example, the chase card of Sword & Shield: Darkness Ablaze is the Charizard VMAX

Amalia Benavides Aguirre Anhelo, the Painter Anje Falkenrath Anje, Maid of Dishonor Anowon, the Ruin Sage Anowon, the Ruin Thief Arnyn, Deathbloom Botanist Arvad the Cursed Ascendant Evincar Astarion, the Decadent Baron Bertram Graywater Baron Sengir Bartolom del Presidio Carmen, Cruel Skymarcher Clavileo, First of the Blessed Cormela, Glamour Thief Crovax the Cursed Don Andres, the Renegade Drana and Linvala Drana, Kalastria Bloodchief Drana, Liberator of Malakir Drana, the Last Bloodchief Edgar Markov Edgar, Charmed Groom Elenda and Azor Elenda, Saint of Dusk Elenda, the Dusk Rose Etrata, Deadly Fugitive Etrata, the Silencer Evelyn, the Covetous Evereth, Viceroy of Plunder Felisa, Fang of Silverquill Florian, Voldaren Scion Fumulus, the Infestation Garza Zol, Plague Queen Ghalta and Mavren Henrika Domnathi Henrika, Infernal Seer Irini Sengir Ivora, Insatiable Heir Jeleva, Nephalia's Scourge Kalitas, Bloodchief of Ghet Kalitas, Traitor of Ghet Kamber, the Plunderer Kazarov, Sengir Pureblood Kinzu of the Bleak Coven Kirol, Attentive First-Year Kirol, History Buff Licia, Sanguine Tribune Lord Xander, the Collector Luis, Pompous Pillager Mari, the Killing Quill Mathas, Fiend Seeker Mavren Fein, Dusk Apostle Mirko Vosk, Mind Drinker Mirko, Obsessive Theorist Mirri the Cursed Monoxa, Midway Manager Morbius the Living Vampire Morlun, Devourer of Spiders Nazar, the Velvet Fang Odric, Blood-Cursed Olivia Voldaren Olivia, Crimson Bride Olivia, Mobilized for War Olivia, Opulent Outlaw Parnesse, the Subtle Brush Rayami, First of the Fallen Rodolf Duskbringer Runo Stromkirk Sauron, Dino Devotee Sengir, the Dark Baron

The sorcery-speed restriction of equipment holds this back, but being a colorless card is a nod in its favor
It won't change a roll of the planar die, but you might get to say something like "I rolled chaos plus 2," which is a pretty cool thing to say
Quag Feast Quag Feast will never be the coolest card in your deck, but cheap, synergistic removal that scales with the game is so incredible that I cant imagine building a black self-mill deck without at least a copy