Normal Monsters have 1 Power, Magic Monsters 2, Rare Monsters 10, Unique Monsters 20, and Players 5
"per Enemy Power" in Path of Exile doesn’t currently exist as a straightforward scaling mechanic. While your proposed system with different power values assigned to monster types is interesting, it doesn’t directly reflect any existing mechanics in the game.
However, several existing mechanics interact with various factors that could be considered similar to a "per Enemy Power" system:
1. Monster Density: Increased density of monsters indirectly correlates with higher "encounter power" as you face more enemies simultaneously. Strategies like Breach League mechanics or maps with high pack size modifiers capitalize on this concept.
2. Area Level: Monsters in higher-level areas have increased health, damage, and resistances, effectively offering a higher "challenge power" per enemy. Players gradually scale their power through leveling and gear to overcome these stronger foes.
3. Aura Effects: Several skills and ascendancy classes grant auras that affect enemies within their radius. Auras like Determination (increased armor) or Enfeeble (reduced attack damage) modify enemy "power" within their influence.
4. Difficulty Modifiers: Players can choose map modifiers that increase enemy difficulty, essentially scaling their "power" further. These modifiers also offer increased rewards to incentivize the challenge.
5. Specific Skills and Items: Some unique skills and items scale their effects based on specific enemy traits like rarity, monster type, or proximity. While not a universal "per Enemy Power" system, they offer similar gameplay concepts.
While your proposed system of assigning explicit power values might not be directly implemented, understanding these existing mechanics allows you to achieve similar gameplay experiences where enemy difficulty scales to create diverse challenges.