When the player dies in the room with the collapsible stairway, Dirk has a large, bulbous nose as he slides down.
The background changes in the room with the "drink me" sign. If the player dies in the "drink me" room, the sign in the background of the room no longer says "drink me", it says "eat me" and there's a loaf of bread with a knife in it instead of the potion.
When Dirk chases the floating pot of gold with his sword attached to it, you can see his holster still has a sword in it.