Half Year Anniversary is an event to commemorate the sixth month anniversary of the Global and TW servers of Arknights and spans across three parts.
Daily Mission
During the event, the following resources are added as the reward for Daily Missions:
| Day 1 and 2 |  6  2  3  10K  6 |
|---|---|
| Day 3 and 4 |  6  2  3 10K 6 |
| Day 5 |  3  4  2  12  6 |
| Day 6 and 7 |  6  2  3 10K 6 |
| Day 8 and 9 |  6  2  3 10K 6 |
| Day 10 and 11 |  6  2  3 10K 6 |
| Day 12 |  3  4  2 12 6 |
| Day 13 | 2  4  6 20K 12 |
Operators
Headhuntting
- Main article: Headhunting/Banners/Former/2020
The Drillelectric headhunting banner is featured.
Half Year Anniversary Headhunting Pack
During the event, the Half Year Anniversary Headhunting Pack is available for purchase in the Packs Store for US$25.99.
Once purchased, the player can choose one of the three Headhunting Permits listed below. All three act as a 
Ten-roll Headhunting Permit with one exception; a 6★ Operator is guaranteed to appear on any of the 10 pulls with it, selected at random from the available possibilities:
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|
 |
|
 |
- Pulls from all three Headhunting Permits listed above are not counted towards the pity system for other banners and getting a 6★ Operator from them will not reset the pull count, so using them will not compromise the player's pity on other banners.
- The Half Year Anniversary Headhunting Pack can only be purchased once and the chosen Headhunting Permit will expire at September 2, 2020 if not used up until then.
- Main article: Ancient Forge
Lantern Festival Treasure
Collect 
Lantern Festival Treasure by completing Daily and Event Missions to claim the following rewards:
300 
|
20 |
| 600
|
10 |
| 900
|
 5 |
| 1200
|
 1 |
| 1500
|
10 |
| 1800
|
 5 |
| 2100
|
 20 |
| 2400
|
1 |
| 2700
|
 200 |
| 3000
|
 10 |
| 3200
|
 5 |
| 3400
|
1 |
| 3600
|
|
| 3800
|
 1 |
| 4000
|
 1 |
| 4200
|
1 |
| 4400
|
 |
| 4600
|
 1 |
| 4800
|
30K |
| 5000
|
 |
Each excess Lantern Festival Treasure will be converted into 20 
at the end of the event (given as an in-game mail).
Missions
Daily
During the event, the rewards for Daily Missions are changed to the following:
| #0 | 500 |
|---|---|
| #1 |  3 |
| #2 | 1K  2 |
| #3 |  40 |
| #4 | 1 5 |
| #5 | 2K  3 |
| #6 | 50 |
| #7 |  1  5 |
| #8 |  100 |
| #9 |  5 600 |
| #10 | 60 |
Event
| Mission | Reward |
|---|---|
Spend a total of 600  .
|
50 |
| Spend a total of 1200 .
|
100 |
| Spend a total of 1800 .
|
150 |
| Have Operators gain a total of 35000 EXP. | 50 |
| Have Operators gain a total of 70000 EXP. | 100 |
| Have Operators gain a total of 100000 EXP. | 150 |
| Spend a total of 60000 on Operators' upgrades and promotions.
|
50 |
| Spend a total of 120000 on Operators' upgrades and promotions.
|
100 |
| Spend a total of 200000 on Operators' upgrades and promotions.
|
150 |
Spend 800  in the Credit Store.
|
50 |
| Spend 1600 in the Credit Store.
|
100 |
| Spend 2400 in the Credit Store.
|
150 |
| Send 4 Clues to friends. | 50 |
| Send 8 Clues to friends. | 100 |
| Send 12 Clues to friends. | 150 |
| Defeat a total of 1000 enemies in Annihilation missions during the assignment period. | 50 |
| Defeat a total of 2000 enemies in Annihilation missions during the assignment period. | 100 |
| Defeat a total of 3000 enemies in Annihilation missions during the assignment period. | 150 |
| Clear any Main Theme stages 20 time(s). Stages that cost 0 do not count.
|
50 |
| Clear any Main Theme stages 40 time(s). Stages that cost 0 do not count.
|
100 |
| Clear any Main Theme stages 60 time(s). Stages that cost 0 do not count.
|
150 |
| Clear any Supply stage(s) 8 time(s). | 50 |
| Clear any Supply stage(s) 16 time(s). | 100 |
| Clear any Supply stage(s) 24 time(s). | 150 |
| Defeat a total of 3000 enemies. | 50 |
| Defeat a total of 6000 enemies. | 100 |
| Defeat a total of 10000 enemies. | 150 |
| Use Recruitment 10 times. | 50 |
| Use Recruitment 25 times. | 100 |
| Use Recruitment 40 times. | 150 |
| Assign 100 Operators to restore Morale in the Dormitory. | 50 |
| Assign 200 Operators to restore Morale in the Dormitory. | 100 |
| Assign 300 Operators to restore Morale in the Dormitory. | 150 |
| Complete 50 orders. | 50 |
| Complete 100 orders. | 100 |
| Complete 150 orders. | 150 |
| Produce 100 Pure Gold in the Factory. | 50 |
| Produce 200 Pure Gold in the Factory. | 100 |
| Produce 300 Pure Gold in the Factory. | 150 |
| Conduct 1 Clue Exchanges during this event. | 50 |
| Conduct 2 Clue Exchanges during this event. | 100 |
| Conduct 3 Clue Exchanges during this event. | 150 |
| Interact with Operators in the Base to increase their trust 60 time(s). | 50 |
| Interact with Operators in the Base to increase their trust 120 time(s). | 100 |
| Interact with Operators in the Base to increase their trust 180 time(s). | 150 |
Special Drop
During the event, all operations (except Annihilation) will have the 
New Year's Lantern as a Special Drop.