Main Story

The main story is the principal PvE progression and the primary area of the game the Player interacts with. It combines campaign and story elements with a specific reward system and farming area for main Resources. It is advisable that all players focus on this feature as it is mandatory for an optimal progression through the game.
=Structure of the Main Story=
==Story Arcs==
If one were to open the World Map they would find it split into areas with specific titles (e.g.: 'Return of the Queen', 'Infernal Unit' etc.) and then underneath the title, one or several chapters mentioned. These are the Story Arcs. 
* Each Arc focuses on one Story Hero and follows a storyline centered around that hero.
* Completing all Chapters of the Arc will allow the user to recruit the Story Hero for free (or claim 30 Hero Tokens for that specific hero if the player already recruited that hero).
* Story Arcs will always unlock in a sequential order - that is, one must finish the current Arc before the next one is unlocked.
* There is (generally) a minimum player level requirement for each Arc - that is, a player must have reached a specific Player Level before they can begin a Story Arc.
* The difficulty does not scale with player level, but Story Arcs become progressively more difficult. 
==Chapters==
Chapters delve in more detail on the Story of the Hero and follow a rather predictable structure:
* Every Chapter is split into multiple Stages that must be unlocked in-order.
* Chapters also have a minimum player level requirement. The first chapter's requirement always matches that of the Story Arc it belongs to.
* While most of the stages are regular battles, each Chapter features (generally) three Milestone stages in the form of castle sieges.
* Completing stages can reward the player up to 3* (read below above how this works), which in turn advances the Chapter progress bar. At key points, this will reward the player with Chapter chests. There's (generally) a total of 3 chests per chapter. Just like the Daily Mission chests, they contain various rewards.
* Furthermore, every Chapter also features various side quests. These can vary from manually collecting resources from the chapter map to destroying powerful units or having conversations with NPC characters on the map.
* Finally, most Chapters also feature one or more special buildings. Consult specific Chapter Details for more about these. 
==Stages==
Stages represent individual battles between the player and an AI-controlled army.
* Each stage features a predefined team formation (Units + Hero) that must be defeated by the player.
* In order to pass the stage for the first time, the player must defeat the predefined formation in manual combat.
* Fighting in a stage costs the player 6. If the player wins that particular battle, all of the energy remains drained. Otherwise, the game deducts only a penalty of 1.
* Each stage also features a star system that signals how effectively the player has beaten that stage. To unlock stars, the player must manually battle the stage and meet the following criteria at the end of the battle (each adds one star, but in-between fights the criteria are not separately tracked):
** ⭐✩ ✩ Win the battle (so every stage won automatically earns a minimum of 1⭐).
** ✩⭐✩ Win the battle with 2 minutes remaining.
** ✩ ✩⭐Lose 2 or less units.
* Each stage features specific rewards that the user will claim by repeatedly beating that level.
** 1x Primary non-Book Material - this is predefined for each stage and guaranteed on each victory.
** 1x Secondary non-Book Material - this is also predefined and always one tier lower than the primary material. This is not guaranteed by beating the stage and is subject to randomness.
** First clearance of every stage rewards rewards 1 Silver Key.
* Once every 2 weeks, three specific events will be scheduled:
** Wednesday, during Harvesting Fest, Wood & Ore stage rewards doubles.
** Thursday, during Alchemy Fest, Sulfur & Mercury stage rewards doubles.
** Friday, during Gem Fest, Gems & Crystals stage rewards doubles.
* After a stage has been beaten for the first time, the player can skip the manual battle by sweeping. Sweeping still costs but is a fast way of farming materials.
* Some stages (usually 3 per chapter) represent castle sieges(🏰), that with a few exceptions are identical to the regular stages:
** Before beating the stage for the first time, the player will be forced to use the Story Hero. However, this is not to be viewed as a handicap - for this particular battle the hero has considerable power and is balanced to make the battle quite easy. Please note that this does not actually reward the hero to the player permanently.
** The opposing army is always confined to the last two back rows, stationary behind a castle wall until you break the wall itself. The wall features (very weak) ranged units that will attack the player army from afar. However, the player's units will also automatically attack the wall and it is actually very easy to take down.
** Before the wall is taken down, no units are able to teleport in the enemy backline. This is particularly relevant for Devil.
==Scout's letter==
Each chapter have 1 specific Scout's letter, which includes 2 parts: Story and Side quest.
*Story part: as it's name, it tells you about the stories of each chapter.
*Side Quest: after complete stages, the side quest will appear, you need to fight with units, pick the materials, or finding the hidden chest to complete the mission.
=Story Arcs=
Each player begins the Story with Catherine unlocked, as both the leading Hero and the Tutorial Guide in Era of Chaos. Starting from the Infernal Unit Story Arc, each finished chapter awards 100 , other than the last chapter of each Arc which awards the protagonist Hero.
Hero	Arc 	Chapter 	Player Level
 	Evermorn Island 	Chapter 1: Evermorn Island 	1
 	Return of the Queen	Chapter 2: Return of the Queen 	5
 	Return of the Queen	Chapter 3: Guardian Angel 	5
 	Return of the Queen	Chapter 4: Griffin Cliffs 	5
 	Infernal Unit 	Chapter 5: Byrds 	10
 	Infernal Unit 	Chapter 6: Breaking Ground 	10
 	Infernal Unit 	Chapter 7: Erathia 	10
 	Infernal Unit 	Chapter 8: Borderlands 	32
 	Border Battle 	Chapter 9: Lands of Chaos 	35
 	Border Battle 	Chapter 10: Marshland 	38
 	Border Battle 	Chapter 11: Tatalia 	41
 	Border Battle 	Chapter 12: Sea of Ice 	44
 	Magic Reinforcement	Chapter 13: From Day to Night 	48
 	Magic Reinforcement	Chapter 14: Safe Passage 	52
 	Magic Reinforcement	Chapter 15: United Front 	56
 	Revenge of AvLee 	Chapter 16: For King and Country 	60
 	Revenge of AvLee 	Chapter 17: Liberation of the Empire	64
 	Revenge of AvLee 	Chapter 18: Deal with the Devil 	68
 	Power and Magic 	Chapter 19: Neutral Ground 	72
 	Power and Magic 	Chapter 20: Tunnels and Troglodytes 	76
 	Power and Magic 	Chapter 21: The Grail 	80
 	Dragon Slayer 	Chapter 22: Crystal Dragon 	84
 	Dragon Slayer 	Chapter 23: Rust Dragon 	88
 	Dragon Slayer 	Chapter 24: Faerie Dragon 	92
 	Blood of Dragon 	Chapter 25: Survival of the Fittest 	96
 	Blood of Dragon 	Chapter 26: Extend Lead 	100
 	Blood of Dragon 	Chapter 27: Dragon Father's Blood 	104
 	Path to Daybreak 	Chapter 28: Tunnels and Troglodytes 	106
 	Path to Daybreak 	Chapter 29: Deal with the demon 	107
 	Path to Daybreak 	Chapter 30: The King's Salvation 	108