Iron Flask

While holding this brass-stoppered iron flask, you can take a Magic action to target a creature that you can see within 60 feet of yourself. If the flask is empty and the target is native to a plane of existence other than the one you're on, the target must succeed on a DC 17 Wisdom saving throw or be trapped in the flask. If the target has been trapped by the flask before, it has Advantage on the save. Once trapped, a creature remains in the flask until released. The flask can hold only one creature at a time. A creature trapped in the flask doesn't age and doesn't need to breathe, eat, or drink.
You can take a Magic action to remove the flask's stopper and release the creature in the flask. The creature then obeys your commands for 1 hour, understanding those commands even if it doesn't know the language in which the commands are given. If you issue no commands or give the creature a command that is likely to result in its death or imprisonment, it defends itself but otherwise takes no actions. At the end of the duration, the creature acts in accordance with its normal disposition and alignment.
An Identify spell reveals if the flask contains a creature, but the only way to determine the type of creature is to open the flask. A newly discovered Iron Flask might already contain a creature chosen by the DM or determined randomly by rolling on the following table (see the Monster Manual for the creature's stat block).

1d100	Contents
01–50	No creature
51	Arcanaloth
52–54	Bone Devil
55–56	Cambion
57–58	Dao
59	Deva
60–61	Djinni
62–63	Efreeti
64–65	Erinyes
66–67	Fomorian
68	Githyanki Knight
69	Githzerai Zerth
70–71	Glabrezu
72–74	Hezrou
75	Incubus
76–77	Invisible Stalker
78–79	Marid
80	Marilith
81–82	Mezzoloth
83–84	Nalfeshnee
85–86	Night Hag
87–88	Nycaloth
89	Planetar
90–91	Red Slaad
92–93	Salamander
94	Solar
95	Succubus
96	Ultroloth
97–99	Vrock
00	Xorn