Darkest Night

Earn Dark Energy and Dark Cups by completing tasks, you can also get dark energy and dark cups by opening duels chests, dark energy are used to open coffers and dark cups are used at the Darkest Tournament, the more dark cups you got the higher you are in tournament. the 1st to 50th place get Infernal Energy as reward, infernal energy are used to open Infernal coffer. At the end of the daily tournament the dark cups quantity is reseted.

Coffers
Cursed Coffer - 3 pickings, unique common event card is guaranteed, can be obtained with 100 dark energy. Also contains duplicates for Common-Legendary non-event cards that are already owned.

Darkest Coffer - 5 pickings, unique rare event card is guaranteed, can be obtained with 500 dark energy. Also contains duplicates for Common-Legendary non-event cards that are already owned.

Infernal Coffer - 10 pickings, unigue rare and common event cards are guaranteed, unique legendary event card is possible, can be obtained with 2 infernal energy. Also contains duplicates for Common-Legendary non-event cards that are already owned.

Energy
The event features two types of Energy. Dark energy and infernal energy.

Along with Energy you get Dark Cups for Dark Tournament rating of the same amount as dark energy.

Tasks
you can get dark energy and dark cup by completing task, the tasks won't reset at the end of the daily tournament, here is the list of tasks.

10 - Level up a dark card

20 - Seduce any card 3 times (can be three different cards)

30 - Win 5 duels

40 - Win City 16.2

50 - Open 4 boxes (bronze, silver, or golden boxes)

60 - Level up dark cards 5 times (can be different cards)

70 - Win Forest 5

80 -  Win 10 Duels

90 - Win Forest 9.2

100 - Get 30 rare cards duplicates

110 - Open 4 chests (in duels)

120 - Win Forest 10.2

130 - Get 50 common cards duplicates

140 - Open Cursed Coffer

150 - Reach Master League 1

160 - Get 10 epic card duplicates

170 - Level up 10 epic cards

180 - Win Forest 14.3

190 - Open 8 chests in duels

200 - Open Darkest Coffer

210 - Get two legendary card duplicates

220 - Reach Master League 2

230 - Get one Epic dark card duplicate

240 - Get 10 rare dark card duplicates

250 - Seduce cards 5x

260 - Spend 3400 Dark Energy

270 - Reach Master League 3

280 - Level up 10x epic cards (can be different cards)

290 - Win Sands 4.5

300 -  Reach Champion League 1

310 - Have 3-star Outworld Devourer or Moiru card

320 - Have 4-star Epic card (Bugged? I have a 5 Star Forest Spirit that is Epic, but the task still shows incomplete.  I had to seduce another Epic card to 4 stars before task shows completed.)

330 - Win Sands 9.2

340 - Reach Champion League 2 in Duels

350 - Have 3-star Fallen Angel or Swamp Witch card

360 - Have  Soul Catcher card (Bugged? I don't have a Soul Catcher card but the task shows 23/1 completion.  When I finished task 350, it tells me 360 is completed and moved me straight to task 370.)

370 - Get 4 Legendary card duplicates

380 - Win Sands 12.1

390 - Reach Champion League 3 in Duels

400 - Open Darkest Coffer 3 Times

410 - Win A Prize at the Darkest Tournament (Bugged? Shows 0/1.  But once I finished 400 it tells me 410 is completed.  I'm guessing the system remembers your previous tournament wins but the display bar isn't showing.)

420 - Open Cursed Coffer 5 times.

430 - Win Sands 13.2

440 - Reach Legendary League I in Duels

450 - Open Silver Box 15 Times

460 - Level up Dark cards 15 times. (Bugged? The task was completed after I leveled up 10 dark cards.)

470 - Get 10 Legendary Card Duplicates

480 - Have Bone Talker Card (Refresh. Need to refresh your browser once you have all 6 cards before Bone Talker card will show up and complete the task.)

490 - Reach Legendary League II

500 - Finish Sands 16 Battle (This is the last task.)