When player attacks a monster, it would be nice if traits of monster(lvl, health, attack, defense) display under the player panel (in left corner of the gui).
I don't think this is a good idea.
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Yes maybe but in this game, the information of monster's level can't be found quickly. Especially when we want to escape them.
If we want to give a hint about the danger levels, one possibility would be placing a skull next to the attack cursor (or some other graphicsl indicator), if the monster is higher level than the player. I don't like giving too detailed information either, like exact stats. They are implementation details. The monster level, however, is available from the game directly, so tying a danger hint to that is not out of question.
After reflection, the panel monster is too invasive if it'll be implemented in the game. On the other side, I continue with the idea of the monster level: your idea to resolve this is not bad, it is already an important update to inform the player more quickly than previously(with the right-clic and Info). Here if it'll be implemented, the information about the monster's level is direct: just put the cursor on it.
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