It was a little clunky and slightly too expensive, but it got the job done
While quite a bland card the sheer number of targets it can hit means it does offer lots of choices
Here are two decklists I've won tournaments with a Red-White Aggro Burn deck and an Azorius Control deck, each with vast differences in the number of cards I played in their sideboards: Boros Burn | Modern | Roman Fusco, SCG IQ/1st Creatures (12) 4 Eidolon of the Great Revel 4 Monastery Swiftspear 4 Goblin Guide Instants (16) 4 Lightning Bolt 4 Lightning Helix 4 Boros Charm 3 Searing Blaze 1 Shard Volley Sorceries (12) 4 Rift Bolt 4 Skewer the Critics 4 Lava Spike Lands (20) 3 Mountain 4 Sunbaked Canyon 4 Inspiring Vantage 3 Bloodstained Mire 2 Scalding Tarn 2 Sacred Foundry 2 Fiery Islet Sideboard (15) 4 Smash to Smithereens 4 Skullcrack 3 Kor Firewalker 2 Path to Exile 2 Searing Blood With the Burn deck being a dedicated strategy of every card trying to deal three or more damage to my opponents, my sideboard options were very limited

At a reasonable cost of 4 mana, the One Ring saves you from your enemies the moment you cast it, and allows you to get ahead quickly by giving you a big card advantage
Making a player lose three life for every land played adds up quickly, and the counters let Ob Nixilis deal the last points of damage itself
Awakening ZoneIt ramps you well and you can abuse Skullclamp with this