Martial Archetype: Knight of Steel and Stone
A subclass for EnderDwarf
Wizard's Bane. When you choose this archetype at 3rd level, you discover secret techniques that protect you from the sinister influence of wizardry. You have advantage on all saves against magic, are immune to the spells Magic Missile and Power Word: Kill, and any attempt to Wish direct harm against you automatically fails.
Runic Languages. Also at 3rd level, you learn to read, write and speak Dwarvish. If you already know Dwarvish, you may choose any other language instead. Furthermore, you learn one master rune, as per the Rune Scribe prestige class. You cannot do anything with it at this point, except use it as a prerequisite for entry into that class.
Spirit of the Mountainhome. At 7th level, you become suffused with the legendary resilience of the dwarves, even if you are not one yourself. You can never become exhausted while you are in mountains or caves.
Dwarven Taunt. At 10th level, you learn a selection of taunts that will distract anyone who hears them. As a bonus action, you may taunt one creature within 60 feet of you. It must be able to hear you, but it need not understand your language. It immediately loses Concentration, with no save allowed. You can use this ability a number of times equal to your Charisma modifier (minimum 1) and regain expended uses on a long rest.
Fists of Stone, Will of Steel. Beginning at 15th level, any bludgeoning damage you inflict automatically bypasses all resistances and immunities. Furthermore, your weapon attacks cannot be blocked or parried in any way, including by the Shield spell.
Knight of the End Times. By 18th level, you have become a paragon of knighthood. You are immune to the charmed, frightened, paralysed and restrained conditions, and cannot be fooled by any illusion created by a hostile creature or effect.
I'm not 100% sure about the high-level effects, but it's a start!