I said: "If a mage is perma invis like you say, then they are not going to be in a situation where you can catch them even if you can see invis."

You said: Why? What does that even mean.

What I mean is:
- A mage can't be permanently invis if they are ranking or spamming combat spells.
- if they are not ranking or spamming combat spells you are unlikely to be able to attack them.
- this is because they will be in their guild, somewhere you can't reach, or somewhere you can't sneak up on them.

So having detect obvious won't help unless they are exposed, and they will pretty much only be exposed and invis if they are resting from ranking. And if they are just resting from ranking, you don't need detect invis to kill them. You need to wait until they are visible because they are ranking. That gives you the distraction you need for your ambush.