Available after beating stage 4-36.
The Resonating Crystal is a place where the player's five best heroes are set in the "Pentagram".
The slots available are for the other heroes from the roster: the player chooses which one is to be raised to the level of the lowest hero in the Pentagram.
While in the slot, a hero cannot be levelled up the classic way in the Hero menu.
When removing a hero from a slot, the cooldown of 24 hours will apply before the slot is available again.
This cooldown can be skipped using 100 Diamonds.
More slots can be unlocked using Invigorating Essences. Invigorating Essences can be found harvesting AFK Rewards after finishing Chapter 5 and by completing campaign quests rewarding it (e.g. level up your heroes on the crystal to a specific level).
After reaching level 240 with all your heroes on the Crystal levelling single heroes won't be possible anymore. Instead, you will be able to level up the Crystal itself in effect levelling all heroes currently in slots.
The maximum level of your crystal will be determined by the number of heroes ascended to Ascended level (white/crystal frame), each hero giving +5 maximum levels (e.g. when you have 5 ascended heroes your maximum level of the Crystal is 265). Currently, the maximum level of the Crystal is 410, it will be increased when new Ascended tier heroes will be added to the game.
Upgrading crystal at lvl 240
After you level up 5 heroes to lvl 240, a new button will be added at the bottom of the resonating crystal screen.
Clicking this button will play a fancy animation and permanently modify the resonating crystal interface:
- 5 more slots are added to the resonating crystal.
- 5 heroes atop of the resonating crystal are removed and assigned to these slots.
- Curved progress bar is added below the resonating crystal instead of heroes.
- New "strengthen crystal" button is added to the bottom of the interface.
Strengthening crystal beyound lvl 240
For each ascended (white) characters in your possession you can increase the crystal level (and level of all characters added to crystal slots) 5 more times. Since you need at least 5 chars to be ascended in order to have 5 240 chars this gives you a minimum available level as 240 + 5*5 = 265.
Click on the "strengthen crystal" button at the bottom will spend specified amount of gold and hero exp and increase the curved progress bar below the crystal. You need to strengthen crystal 10 times to level it up, with each strength increase cost the same amount of gold and hero exp, but last one also has an additional cost in hero essence.
Crystal level up resource cost
Table below shows total cost for 10 strength increase required to level up a crystal. It's a work in progress:
Here is a guide to Resonating Crystal by Bahraldiyn, ID: 11079601, S108
Edited and added additional content by Vagabond ID:15818929, S153
Added info about resonating crystal beyound lvl 240 by grigoryvp, ID: 5357153, S52
Feel free to fix any errors you may find.