Heroes levels are increased by gaining Experience in Raids, Dungeons, and Here Be Monsters or by consuming Tomes. At every 20th Hero level, a Star level Upgrade will appear requiring Gold, Honor Badges and Fires
in order for the Hero to gain additional Hero levels. Note that not
upgrading star level will result in Hero no longer gaining experience.
Heroes can be purchased and upgraded in the Heroes Altar. You can buy a Hero four ways, using different resources:
Gems: Gambling, the 'real' numbers are only known by IGG, however a study suggests that a gem roll gives the player a 5% chance to receive a Legendary Hero, a 60% chance to receive an Elite Hero, a 10% chance to receive an Ordinary Hero, and finally a 25% chance the receive a sacrifice hero (with a 15% chance of a Gelatinous Champion and 85% chance of Crystal Ooze). The data also suggests that when receiving a Legendary Hero, the chance of it being a gem roll only hero (i.e. Pumpkin Duke, Snowzilla, Cupid, Aries, Vlad Dracula, Orksbane and Santa Boom)
are smaller than of it being a shardable hero, however there is not
enough data available for this to be statistically proven. [1]
Honor Badges: Gambling, gives a high chance to receive a Slime or Ordinary Hero.There is also a small chance that you can get an Elite Hero and an extremely low (nearly zero) chance of getting a Legendary Hero.
Shards: Selection, you can choose which hero you wish to acquire by purchasing it.
There are also heroes that can't be obtained these ways. Spirit Mage and Minotaur Chieftain are rewards for purchasing specific amount of gems and Moltanica is reward from events.
Duplicate heroes cannot be stacked, i.e. You cannot have more than one of the same type Hero fighting or defending from the Hero Bases and Hero Expeditions, but you can have duplicate heroes occupying Tower Garrisons.
Sacrifice
Sacrifice Heroes are heroes that are used (consumed) to
increase other Heroes' skill levels. They can not be used in battles or
for tower garrison purposes.
Ordinary Heroes have the
lowest stats, but are inexpensive and are therefore good for beginners.
They introduce the player into the game, but they are not especially
strong.
Boss are classified as Heroes too, but on the enemies' side. They are
special heroes where designated on different features of the game. They
cannot be attained on any types of purchases but they can be seen on
the assigned features like Here Be Monsters , Team Dungeons and Challenge A Boss fights.
There are some heroes not yet released, but there are clues. For example, the "Pirate Captain" is on the Loading Screen V1.2.24 and 1.2.25 as seen in the image below.
In fact, Pumpkin Duke
has been the new model of Pirate Captain since the Halloween event, but
now there are some rumors about Pirate Captain being a completely new
and different hero from Pumpkin Duke that will be released in the future.
The heroes shown below are extracted from the Chinese version of the
game, but there are already pieces of them in English Version (skill,
images, names...).