Dragalia Lost's Halloween event for 2020 is Postmortem Panic, a series of increasingly difficult challenges with a slew of rewards. It's live from October 12 at 2 a.m. through October 19 at the same time, but the event rewards can be claimed until October 26 at 1:59 a.m.
Postmortem Panic divides its missions by difficulty. Completing all the challenges at one tier earns battle charts and stratagems for unlocking the next level of quest.
Some of these are special dragon battle challenges, pitting adventurers against the toughest of foes like Astral High Mercury.
Victory earns wind and water tomes to unlock new skills for certain characters, while completing quests earns primal crystals used for treasure trading.
[Source: Nintendo of America]