Which system is the term keeper from?

I don’t think I’ve seen that version of the Addams Family

It depends because official magic item prices are vague and bad, but Sane Magic Item Pricing has items that go up to 165,000gp and considers the staff of the magi too powerful to price.

Considerably more given you’ll generally use it on a bad roll.

That Venn diagram is a circle.

Potala Palace in Tibet

The Sumela monastery in Turkey’s black sea province of Trabzon

Mount Thor in Canada Featuring Earth’s greatest vertical drop of 1,200 m (4,100 ft), with the cliff overhanging at an average angle of 105 degrees (15 degrees from vertical)

You’ll get tired of winning.

Surprisingly those two aren’t the ones that invaded Assyria.

Those aren’t mutually exclusive.

“Not if I cast shield”

-My level 20 warforged armour dipped wizard in a game where the DM was quite generous with magic items