6000-power leaders have an advantage on hitting an opponent's leader, requiring them to utilize +2000 counters out of hand just to negate the damage to life while your leader only has to counter out of a 6000 attack with a +1000 counter
Jeweled Lotus is the comparison people want to make, but that was significantly rarer, needing 400 packs to get there

Favor of the Mighty Feudkiller's Verdict Firbolg Flutist Fleshpulper Giant Flowstone Giant Fomori Nomad Frost Giant Frost Titan Frostfist Strider Frostpyre Arcanist Furnace Host Charger Furystoke Giant Galecaster Colossus Galvanic Giant Gangrenous Goliath Garenbrig Paladin Giant Harbinger Giant's Ire Gingerbread Hunter Goliath Daydreamer Goliath Paladin Gorm the Great Grabby Giant Grasping Giant Grave Titan Grixis Slavedriver Haazda Vigilante Hamlet Glutton Hamletback Goliath Hammer Dropper Hammerfist Giant Hammerheim Deadeye Hearthcage Giant Heartwood Giant Helldozer Highland Giant Hill Giant Hill Giant Herdgorger Hill Gigas Hillcomber Giant Hired Giant Hotheaded Giant Hovel Hurler Howling Giant Hundred-Handed One Impelled Giant Inescapable Brute Inferno Titan Iron-Fist Pulverizer Ivory Giant Ivory Guardians Jareth, Leonine Titan Jtun Grunt Jtun Owl Keeper Kalemne's Captain Kalemne, Disciple of Iroas Karplusan Giant Knight of the Last Breath Kroxa and Kunoros Kroxa, Titan of Death's Hunger Kuldotha Ringleader Lairwatch Giant Loafing Giant Loamdragger Giant Lotleth Giant Lowland Giant Lowland Oaf Lunk Errant Magma Giant Marble Titan Marshdrinker Giant Marshmist Titan

It included what I genuinely think is one of the most beautiful and evocative cards of all time, Lingering Mirage by Jerry Tiritilli
Like all decks, there are upsides and downsides