At the beginning of the next end step, destroy that creature if it attacked this turn
Karlach makes for a compelling Gruul stompy or Boros go-wide commander, and prices for her card haven't ever fallen below a dollar on MTG Goldfish
I kind of view Quicksilver Amulet as a staple for Commander / EDH decks, which most players stuff with large, high-casting cost creatures

Azami, Lady of Scrolls Azami, Lady of Scrolls | Illustration by Ittoku Commander (1) Planeswalker (2) Jace, Wielder of Mysteries Narset, Parter of Veils Creature (21) Archaeomancer Baral, Chief of Compliance Cyclone Summoner Glen Elendra Archmage Jace, Vryn's Prodigy Laboratory Maniac Lighthouse Chronologist Malevolent Hermit Patron Wizard Sea Gate Stormcaller Snapcaster Mage Sower of Temptation Spellseeker Thassa's Oracle Tribute Mage Trinket Mage Triskaidekaphile Trophy Mage Vedalken Aethermage Vendilion Clique Venser, Shaper Savant Instant (24) Aetherize Arcane Denial Archmage's Charm Blue Sun's Zenith Brainstorm Counterspell Cyclonic Rift Dig Through Time Dispel Dramatic Reversal Frantic Search High Tide Long-Term Plans Mana Drain Mental Misstep Muddle the Mixture Mystical Tutor Negate Pact of Negation Pongify Rapid Hybridization Reality Shift Swan Song Turnabout Sorcery (4) Expropriate Fabricate Step Through Windfall Enchantment (4) Back to Basics Mind Over Matter Mystic Remora Rhystic Study Artifact (11) Arcane Signet Extraplanar Lens Isochron Scepter Mind Stone Mana Vault Sapphire Medallion Sensei's Divining Top Sky Diamond Sol Ring Thought Vessel Throne of Eldraine Land (33) Snow-Covered Island x27 Mystic Sanctuary Nykthos, Shrine to Nyx Path of Ancestry Reliquary Tower Riptide Laboratory Seat of the Synod Prior to my ventures into the world of Urza, Lord High Artificer, I was deep in the trenches of Azami, Lady of Scrolls wizards

Gemstone Mine is unique in that it has a limited number of taps due to relying on mining counters that reduce every time it is tapped, it enters with three counters and gives one mana of any color when tapped
Rakdos Charm is cheap and instant artifact removal therefore trumping things like Torch Fiend in that role yet in its other, perhaps more situational uses the Rakdos Charm is not nearly as dull as a 2/1 for 2 offering you far more power