Man.. I really, really hate when games do this. If I wanted to run & hide from invincible foes I'd play Amnesia.
I remember playing Lands of Lore, one of my favorite games, and one of the enemies you have to fight will likely confuse you the arnfirst few times because as far as you are aware it is invincible (honestly I think the creators expected you not to fight it), however it is quite mortal if you know that throwing is EXTREMELY effective in the game (This is because you can throw as fast as you can click, but attacks and magic need to wait a bit).
So at least you aren't playing the "Can I kill this?" game.
I'd list all the things Lands of Lore did wrong but... GOODNESS it is a list. I love it, but it is a love of understanding its many faults... but lets get a few out of the way
1) Dos Era copy protection: For those who don't know what this is... I want you to turn to page 100 of the nearest book and write down the fifth word in the second line on the second paragraph.
2) Inventory management hell: Ohh dear goodness... your entire inventory is basically a single bar that goes on and on that you have to cycle through... Given you never know what is important and it is VERY easy to forget something important... yikes
3) Insane dungeon lengths!: Ok lets not take this lightly... Lands of Lore is INSANELY difficult, it is so difficult what would be "secrets" in one game is "How to play the game" In lands of lore. Thus you BETTER explore every single inch of that dungeon!
4) NO! You don't get to make the keys all daggers that look exactly the same
5) No item descriptions: part of me wants to say, it was a different era and exploring how the game works was part of the fun... and frankly... that is true. Though I found myself hoarding important looking items that were near useless trinkets.
6) Did I mention how relentlessly hard it is? Honestly if you combined a really hard RPG with a really hard point and click, you would probably get this... The SECOND dungeon (mandatory one) is quite difficult and a HUGE ramp up from the last one. Could they really not smash the player's face in? I mean I appreciate the difficulty and I liked how much I had to go through to do it, but that could have been a final dungeon in a much easier game.
7) Spin traps were never fun. It was never fun when Wizardry did it too. Worst of all is that it is one of those things that mess you up because you are on a computer, but where your characters wouldn't be disoriented.
Lay off the Pit traps!: You HAVE to fall in every one... Why are there so many?
9) Wait which cure do I use?: You have five levels of cure... and trust me which one you use is very important... and no it isn't straight forward...