Laboratory

This useful facility allows you trade Guild points, hero shards, and materials for heroes, new essences, and enhancemons.

Event Exchange

This option is only available when there’s an ongoing event. In this example, you can trade in spirit shards for a free SSR character. Event spirit shards are acquired by completing its corresponding mission. Once you have enough spirit shards, trade them in the Laboratory and pay the amount of Gold displayed to get the free SSR character added to your hero box.

Hero Exchange

Same as the Event Exchange above, you can trade in 120 spirit shards of specific advent heroes to get them added to your hero box. You can farm these shards in Multiplayer versions of the advent dungeons that gets rotated regularly. Multi-advent dungeons can only be entered 10 times a day that gets refreshed along with the daily refresh schedule. Take note that the heroes you get from exchanging shards are the same as the ones you’ll potentially get as drops in Single versions of the same advent dungeons.

Essence Exchange

Here you can exchange essences from one element to the next at 500 Gold each. You can also exchange for Rainbow and Advent essences with the exchange rate below:

Rainbow Essence = x5 of each elemental essence + 12,500 Gold

Advent Essence = x10 of each elemental essence + 25,000 Gold

Due to the cost involved for transforming epic essences (Rainbow and Advent), you’re better off farming them and only use this feature if you’re just a few essences away from the amount you need. Elemental Essences can be farmed from SP Essence Dungeons (no run limit) with Rainbow Essences as a rare drop, while Advent Essence can be farmed from advent dungeons at a reasonable amount per run. Essences can also be acquired from other sources such as mission/achievement rewards, adventure map clearing rewards, Pal Lotto/ Roulette prizes, or even bought from the Secret Shop.

Guild Coin Exchange

This allows you to spend your earned Guild Points (acquire by completing daily guild Missions) to exchange for runes and heroes. I’m not sure if the available heroes and runes get shuffled after a certain amount of time but as of this writing, you can get an SSR dark attacker character Cheshire. The 6* version of her can only be bought once, her 5* version can be bought after 5 times, and her default 4* version supposedly unlimited but with a 2x per week limitation. You’ll need multiple versions to enhance the Skills of this character.

As for the runes, you can spend Gold and GP to buy some of the rare runes that you won’t normally get from the rune dungeon or even as reward.

Trade Enhancemon

Enhancemons are fodder monsters that you can use to Enhance your hero’s stats permanently (adds up a purple star to their portrait). They have the same function as advent heroes but you unlike advent heroes, you can’t keep them as standalone characters or use them in battle. You can easily farm R-grade advent heroes but the SR and SSR ones can be tough to farm without a powerful team. Enhancemons serve as the solution to this problem by giving you access to SR and SSR advent hero substitutes albeit at a limited amount per day or week.

You can trade enhancemons using advent fragments and advent essence (both can be farmed from single or Multi (Advent) dungeons)