Every 5th time or so, a notice would appear in console and tell user a QTE is about to happen.
After a countdown something that requires user input launches
The user's performance influences the battle.
Some ideas include....
The monster moves around really fast, you get points every time you can click it.
QTE to determine whether or not attack misses (based on evasion)
Wiggle mouse / click key / click mouse to increase some number that is visualized as a bar opposite the monster's own bar, or a bomb size for example, to influence an attack.
"Increase your critical hit chance! Press "C" as fast as you can!" This increase value of critical hit.
This could be influenced by micro games like Dumb Ways to Die https://www.youtube.com/watch?v=nvZO5pnspo8
This happens like...
Some ideas include....