Immortal King's Detail

There's a hidden level "penalty" when upping an item.

Immortal King's Detail is originally exceptional, so I'm assuming you mean that you upgraded it to elite (

War Belt to

Colossus Girdle).

• When upgrading from normal to exceptional, there's a +5 level requirement modifier to the upgraded base's required level.
• When upgrading from exceptional to elite, there's a +7 level requirement modifier to the upgraded base's required level.
• When upgrading twice from normal to elite, there's a +12 level requirement modifier to the upgraded base's required level.

For unique & rare items, it was always possible (since the pre-D2R days) to upgrade them with the cube, so the in-game item tooltips will correctly include the +5/7/12 level requirement modifier.

For set items, however, it wasn't possible to upgrade them until patch 2.4 in D2R, and in-game tooltips will not accurately include the +5/7/12 level requirement modifier. Item tooltips will show the level requirement without the modifier, but your character will refuse to equip it until you've met the level requirement including the modifier. I've always suspected that it's an oversight, something they forgot about when they coded the game to allow upping set items.

You will be able to equip the upgraded

Immortal King's Detail at level 74 (67 is the base level requirement of

Colossus Girdle, +7 for the exceptional>elite upgrade).

It is mentioned in all the item upgrade recipe articles here at diablo2.io, courtesy of Knappogue, but many sites fail to mention this little detail. You're far from the first to be stumped by this, and you won't be the last, unfortunately.

recipes/recipe-exceptional-version-of-r ... t3300.html
recipes/recipe-exceptional-version-of-r ... t3299.html
recipes/recipe-exceptional-version-of-s ... 85809.html
recipes/recipe-exceptional-version-of-s ... 85808.html
recipes/recipe-exceptional-version-of-u ... t3295.html
recipes/recipe-exceptional-version-of-u ... t3296.html
recipes/recipe-elite-version-of-rare-armor-t3302.html
recipes/recipe-elite-version-of-rare-weapon-t3301.html
recipes/recipe-elite-version-of-set-armor-t785811.html
recipes/recipe-elite-version-of-set-weapon-t785810.html
recipes/recipe-elite-version-of-unique-armor-t3298.html
recipes/recipe-elite-version-of-unique- ... t3297.html

I think they're pretty clear, but perhaps colors can be used grab the viewer's attention, such as to the +5/7/12 values? I dunno, maybe someone else has a good suggestion.