You mean something like this?
It tracks players/bots too but those on your team get non-descript red dots. In team games, players/bots on the other team are a different color.
Don't have a download handy, got it from medor (for those who know who that is) but it's pretty decent.
Yellow dots are monsters close to you, but monsters really high up read as white dots too.
The range on it's fairly close to you, can't extend it, but I've found it handy on large maps with hard to find monsters.
As to blobs (pardon the smaller image):
Back in the good old days of MonsterMadness, that red circle on the left was a radar to detect monsters... from MM only. Although, you could extend the range of the thing... so there's that.