This list has been around for years, and better ones too that go higher, yet they all stop at about the same place. Seems like those who started them never finish them. Pretty useless unless you are new here.
Highland's Longbow: North Midgard level 2: 1,000 coins 2x Serpent Clawblade 1x Chainmail Armor Ebony Knife: South Midgard level 15; 10 million coins 1x Pillager's Tunic 1x Pillager's Axe Njord's Champion: Aegir's Sea level 75: 80 million coins 1x Hurricane Master 1x Royal Hersir Aegir's Trident: Aegir's Passage level 140: 175 million coins 2x Aegir's Warship 1x Hero's Warship 2x War Elephant Skyshine Blade:Vanaheim level 300: 1 billion coins 1x Scroll of Vanir Knowledge (not consumed) 2x Minotaur Hoof Club 1x Thunderstoke Mace Under Giant:Niflheim level 420: 750 million coins 2x Frost Giant 1x Viking Axes (not consumed) Giantsbane: Jotunheim level 600: 3 billion coins 1x Rock Giant Hammer 1x Giant's Blade 1x Blessed Oil Steel Sword: Alfheim level 620: 5 billion coins 1x Alfheim Dagger Set 1x Skull Dagger (not consumed) 1x Viking Dagger (not consumed) Blood Spewer: Nidavellir Level 760: 10 billion coins 1x Cavern King (Craft Item) 1x Dwarven Berserker (I think it's a reward for the Nidavellir Challenge) Hellfire Chariot: Muspell level 900: 15 billion coins 50x Fire Chariot 50x Fire Wingsuit Poison Stroke: Helheim level 930: 20 billion coins 1x Hel's Blade 1x Hel's Tunic 1x Poison Arrows Skymaiden: Vingolf level 1600: 20 billion coins 2x Goddess 1x Sacred Well Aurora Spear: Asgard level 2000: 45 billion coins 1x Odin Favor Charm 1x Iwas Rune 1x Stonecrack Hammer Autumn's Hammer: Midgard - Godly Trials level 2500: 100 billion coins (Thanks to monkhughes for providing the recipe.) x1 Scroll of Vanir Knowledge x1 Thor Amulet x1 Valkyrie Bladestaff Aurora Knight: Alfheim - Godly Trials level 2900: 275 billion coins x1 Grove Knight x1 Elven Captain x1 Sacred Well Stonepillar Axe: Nidavellir - Godly Trials level 3350: 600 billion coins Earthheart hammer battlerune axe viking axes Damned Elven Queen: Muspell - Godly Trials Level 3650: 500 billion coins (Thanks Jerome Griffin) x1 Muspell Specter x1 Golden Apple of Youth Thunderswipe: Asgard - Godly Trials Level 5700: 1.2 Trillion coins Tyrs Warhammer block hammer seax Cyclone Furrow: Hel's Rising Level 6400: 1.2 Trillion coins Garms Collar hammer and chisel spellbook Spirit Stag Required Location: Skadi's Blizzard Level Unlock: Level 6500 Crafting Cost: 1,500,000,000,000 coins Snowcape battle swine Ultimate spear Required Location: Jotunheim World Wall Level Unlock: Level 7600 Crafting Cost: 2,500,000,000,000 coins Mountainblade axe Sigil of Odin