Deathbringer

[ImaDeadMan]

So I was going through the Monster Manuals... why, just why, is the Deathbringer a CR 17 monster? It just doesn't seem like it should be anywhere near that! Yeah it can dispel magic at will and throw a weak burst of negative energy, but an Adamantine Horror can cast Mordenkainen's Disjunction at will as well as Implosion and Disintigrate.

[holywhippet]

Common theory is that the designers of the game rolled a d20 for monster CR until they hit a value that seemed vaguely reasonable.

Ok, honestly the CR for some monsters is all over the place. For a solo encounter the deathbringer isn't that great as the PCs will be smacking it hard, fast and often. Put some lower level undead in front of it though and the deathbringer can start stripping away the PCs magical buffs before engaging in melee.

[Silva Stormrage]

CR is a bad estimate and there are plenty of weak for their CR and overpowered for their CR (See Adamantine Horror for overpowered for their cr) use it as a ballpark figure than make sure to check wether or not its power level is appropriate and then adjust it to match your party's optimization level and competence level.