Kher Keep is unique among fortresses: impervious to aerial assault but defenseless from the ground.

Kobolds of Kher Keep

Mystery Booster 2

Murders at Karlov Manor Commander Tokens

March of the Machine Commander Tokens

Phyrexia: All Will Be One Commander Tokens

Dominaria United Tokens

Although originally printed with a characteristic-defining ability that defined its color, this card now has a color indicator. This color indicator can't be affected by text-changing effects (such as the one created by Crystal Spray), although color-changing effects can still overwrite it.