Sense Materia. It's pretty good and useful and I like it, just like I love Scan and all other equivalent abilities in RPGs.

However, as I'm sure you all have, eventually the thing becomes useless in this particular game. I used to think it was some intentional game flaw, to keep things difficult. Later bosses aren't going to have obvious weaknesses listed out for your or whatever.

However, according to a modder I was just reading, it is literally impossible to Sense a monster with more than 65,000 HP. The game just plain can't display it. It will show a wrong number if you try to hack it.

So, good job Square. You screwed up so bad, not even the modding community can fix it.