It's largely the same system. You can play as the Greeks, Norse, or Egyptians. Each civilization has the choice of 3 major gods (is Zeus, Hades, or Poseidon) that choice is kinda like choosing your civilization in AoE. Instead of going feudal age to castle age, you choose a different minor god to worship. Each god gives you a different god power and mythological unit (Cyclops, trolls, anubites, etc). The final civilization upgrade allows you to build a building that unleashes a titan on the map.

There is a new currency called favor that is used to research some improvements unlocked by worshiping specific gods and to train mythological units.

The types of games are largely the same as AoE, with different maps. The campaigns are a lot of fun. It's a great game, especially if you like mythology. The stories are original and not based on the original myths, but you can learn some of the myths of heroes, mythical creatures, and the gods by right-clicking on them. The campaigns walk you through how to play and through the features that are different from AoE.

You can choose varying difficulty for the scenarios and can choose the difficulty of the computer players when playing a random map. This makes it about as complex as Age of Empires. However, just as with online AoE, the player vs player can have a steep learning curve if you're matched against people that have been playing a long time.

Age of Empires and Age of Mythology play similarly, where it's easy to cross from one to the other with many similar human units shared between the games. I think it's definitely worth a look into! Even the remake that's already on steam is worth it in my opinion.