Mouseferatu
Hero
I'm honestly having trouble recalling the last time I ran a medium- to long-term campaign that didn't involve a lich on some capacity. I'm almost, but not quite, as bad with mind flayers. I just really, really love building plots and schemes around those guys. 
I'm curious what monsters other DMs find themselves using as go-to options perhaps more often than strictly necessary. (And I don't just mean "This creature appeared briefly in a random encounter" or the like, but as actual plot-centric or adventure-focused antagonists or NPCs).

I'm curious what monsters other DMs find themselves using as go-to options perhaps more often than strictly necessary. (And I don't just mean "This creature appeared briefly in a random encounter" or the like, but as actual plot-centric or adventure-focused antagonists or NPCs).