One of the more unique features of PoE is its economy. Rather than hoarding gold dropped by enemies, it uses a bartering system. There are many consumable items that grant special effects (e.g., increasing the quality of gear, identifying items, etc.), but you also have to trade those items to merchants to purchase anything. It seems to keep inflation down as far as I can tell, and makes it a little harder to just outright grind for stuff.
Path of Exile contains a fairly solid three-act campaign, and as you might expect with its inspiration, completing it unlocks a higher tier of difficulty. Cruel and Merciless difficulties up the ante slightly, since death now carries an XP penalty. Once you've cleared Merciless mode, you'll unlock the Eternal Library - granting you access to Maps.
Maps are randomized bonus zones that carry a high degree of difficulty, and they drop from monsters above a certain level. Right now, maps are considered PoE's endgame, but there's a lot of variety and challenge, so they can keep players busy.
League of what now?
If playing the standard campaign, you may (currently) create characters in one of four Leagues.
- Standard: This is the default league with no additional conditions.
- Anarchy: Similar to the Standard league, the main difference is that there are 13 "Rogue Exiles" (basically, named NPCs with player skills) that can show up and beat you soundly.
- Hardcore: If you die, your character is permanently moved to the Standard league.
- Onslaught: Same as Hardcore, but enemies move 20% faster.
These primary Leagues are simply different ways to play the regular campaign, and rotate every so often. If you want a greater challenge, or want to get competitive, you'll want to enlist in the Race Leagues.
In addition to the standard campaign Leagues, you can also choose to join Race Leagues, which are Path of Exile's ladder system. A Race is basically a challenge, lasting anywhere from 12 minutes to 30 days, where players compete to meet conditions such as achieving a certain level, being the first player to clear out zones of monsters, or completing quests. Meeting the conditions of a race gives you ladder points, and at the end of each race the top players will receive special items.
Race Leagues also have their own special rule sets, such as the following:
- Blood Magic: Instead of consuming Mana, all skills consume Health instead
- Cutthroat: You can enter other players' instances at will, and whenever a character dies, all of their equipment is dropped.
- Turbo: Monsters move 60% faster. Oh snap!
Combine this stuff with the Maps mechanic, and there's plenty of replayability to be found in PoE.