optional and challenging way to speed up runs and increase difficulty

on each level, a few slow but high HP enemies appear that actively avoid the player, and eventually exit if they aren’t killed. if the player chooses to undertake the challenge of killing these enemies while still fighting off the normal mobs, it will trigger an increase in the pace and difficulty of the current and subsequent levels of that dungeon. The more of these mobs you kill, the more of an effect it will have.

This will allow good players to be more challenged more frequently, and to finish their runs faster, but only if they have the skills to pull it off. Worse players or those who don’t want a challenge can simply choose not to kill these special mobs, or they can fine-tune their challenge by only killing some of them. This will make each set of dungeons more fun and challenging for a greater cross section of players, and it will give players the motivation to increase their skills and their gear so that they can finish dungeons quicker and get more done in less time. Not only does killing the mobs increase the overall challenge, but killing the mobs is itself a challenge that will make the easier levels more interesting and engaging because there will be yet another objective to pursue while still doing the normal killing and collecting.