In Lost Ark, there is a daily login bonus that you receive every day for logging into the game. As a reward for logging into the game ten times this month, you’ll receive some Aura of Resonance Restoration Elixirs. These items are given away as special login items, making it difficult to ever come across any of them. As this is likely the first time many players are seeing these potions, they might be confused as to what they are doing.
The description of the potions reads: “A mysterious elixir that can restore the aura of resonance. It restores 50 Aura of Resonance when used.” Aura of Resonance is what you use to enter Chaos Dungeons and earn rewards. Normally you only gain 100 Aura of Resonance per day and lose 50 Aura of Resonance per run. Because of this, you typically only enter Chaos Dungeons twice a day.
However, these potions restore 50 Aura of Resonance, meaning you can get another Chaos Dungeon Run with full rewards. If you get five potions for the login reward, you’ll also get five Chaos Dungeon runs. This maximizes the amount of honing materials you can obtain to upgrade your gear.
Note: These potions expire after seven days, so don’t leave them in your inventory. Use them as soon as possible and don’t let them expire, as losing five extra runs is extremely inefficient. You should also know that you can also complete Chaos Dungeon without Aura of Resonance, although instead you will get other rewards at a slower pace.
https://www.gamepur.com/guides/what-are-aura-of-resonance-recovery-elixirs-in-lost-ark What are Aura of Resonance Recovery Elixirs in Lost Ark?