The Army is Floored?
The brave band of adventurers have delved in to the uncovered depths beneath a graveyard, searching for the powerful necromancer Morbent Fel. After some dangerous encounters with the undead denizens in the area they enter a large set of rooms with metal grates in the floor. Beneath the grates hold more, powerfully-mutated undead. Thinking that there may be a master switch to release all the grates, the adventurers use their skills and equipment to tie as many of them shut as they see prudent.
Not long afterwards, Morbent Fel is found. As they approach, he does what any evil mastermind does: he monologues. Our heroes have other plans, though, and it takes some quick, or a lack of, thinking to distract him so that they can expose his weakness.
The necromancer starts his monologue, 'Fools! All you have done is enter my lair, brought yourself to me for your own destruction. Even now, my undead army is ready to be unleashed!'
'We've tied it to the floor!', butts in Metrius.
'... Uh...'
And in the confusion, initiative is rolled.