The new RMG will add new Heroes V maps and increase the replayability of the game. Possible rewards are no longer static amounts of gold and resources, but can also include artifacts, spells, scrolls, wands, prisoners and small permanent skill boosts. The resistance will scale up to the player's strength, no matter how long the game takes.
Armies and rewards will never be exactly the same again no matter how often the player plays a map. The contents of the new locations is completely dynamic and follows an Oblivion/Skyrim inspired constantly scaling and endlessly randomized system. Treasure vaults and dungeons will now have unique immersive interiors with larger battlefields, growing armies and new obstacles.
In MMH5.5, there will be around ~30 new adventure objects. New features Extended Adventure Map and battlefields