Once you defeat all the boss levels, you can Ascend – which keeps a small section of rewards that accumulate, but starts you out with all maps +2 difficulty.
The game technically has no “end” per se. To get more rewards, you can up your Wrath level and lastly you can also increase the difficulty using runes – which grant increased XP gains to level even faster. You will have to do levels more than once to get a flawless run (losing no lives), and many maps have objectives / challenges that give great rewards that add a twist / difficulty level. Dungeon Warfare 2 is a great Tower defense game but it is not an easy game.
