Olden Keystone
The Olden Keystone is a static device in the Reclamation Algorithm game mode of Arknights, introduced in Tales Within the Sand.
Olden Keystones only appear on Mountain Passes, where destroying the Pass' respective Keystone is required to conquer it and granting access to other regions of the overworld. This is easier said than done however, as while the Keystone does not have much HP, it instead requires a certain number of attacks to be destroyed and recover its HP over time; if the player fails to destroy the Keystone in one fell swoop, its HP will be fully restored when the Pass is entered again! This is exacerbated by the fact that Olden Keystones are surrounded by resources most of the time, forcing the player to harvest them first (which may take multiple tries) to clear the path for friendly units to bring it down.
Stats
Range
■ |
Attributes
| HP | ATK | DEF | RES |
|---|---|---|---|
| 600 | 0 | 0 | 0 |
| DP cost | Redeployment time | Block count | Attack interval |
| N/A | N/A | 3 | N/A |
| Addendum | |||
| |||
Skill
 |
Key Passive | |||
|---|---|---|---|---|
| Effect | 
|
|
| |
| Gradually restores own HP. After receiving a certain number of attacks, get destroyed and unlocks a new area | 0 | 0 | – | |