The only reason all my henchmen would be dead is because I had them assigned to retreat at any sign of the hero preventing him from leveling up. So in order to gain exp, he has to go around the towns, slaughtering the locals; the smaller and cuter they are, the more exp. By the time he's leveled up enough to chase down fleeing minions, (they're also assigned to not engage nor defend) leaving the hero to murder helpless "bad guys" when they never actually learn what they have against a minion other than they're attacking him. With the minions not actually engaging the hero, he gains no exp from them.
Leaving the very last save point at the bottom of my long and tedious castle: built from the classic Resident Evil's locked doors and backtracking system along with their limited inventory, joined with Touhou's, dancing in the rain without getting wet, impossibility- My mini bosses would consist of optional bosses from various games like FFVII that take hours to beat upon conditions required, and possessed teammates forcing him to walk over the bodies of friends in order to proceed.
All of his abilities would be extremely brutal and gruesome to the point if there was anyone spectating their mind would break, turning the hero into the type to kill first, listen later. With that mentality I would be waiting in the final room with no words to offer but a prize for defeating me. During the whole battle I would show recordings of his journey up to this point as I taunt and evade him until he goes mad, exposing his latent powers. There I would flip a switch which reveals a treasure chest as I bid my farewell to the hero. Assuming what's inside is the final piece to defeat me, the hero would open it to find a single windowed pane, reflecting his own image. If he truly is the hero, his madness will turn insipid as I make my escape. If he is unscathed by the item, I will either propose he takes my place or take his swift blade with a smile.