What minions can warlocks get on World of Warcraft at what levels

At level one an Imp can be acquired.
Level 10 is when you get a Voidwalker.
At level 20 you get a Succubus.
Level 30 you get to summon a Felhunter.
And if you are specced in the Demonology talent tree you can summon a Felgaurd at level 50. ----------- you can also get an Inferno from a questline and our stronger minion: the Doomguard