Operation guide: DH-TR-1
| Operation | Guide | Story |
The first special tutorial operation in the Dossoles Holiday event, DH-TR-1, titled Just Arrived, introduces the player to High Tides, the Erosion mechanic, and the second type of Elemental Damage introduced to Arknights – Corrosion Damage.
At first Bubble are deployed on E6 and Ernesto Salas explains that the city of Dossoles uses water Arts to simulate the oceanic tides on the Dossoles Lake, which have its own dangers. Right as a Tactical Hound spawns from F11, a rippling water visual can be seen at the bottom of the screen, and shortly after, most of the melee tiles are submerged in saltwater. This is how High Tide works; periodically in DH operations, parts of the map will be submerged in saltwater that prevents friendlies from being deployed on the submerged tiles.
Notice a circular dark blue meter is displayed on Bubble as it goes drained over time and whenever the Hounds attack her. Ernesto then informed that the High Tide's saltwater is strong enough to erode equipment and will be made worse when the eroded ones are in combat; Friendly units being submerged by a High Tide will be inflicted with Erosion where they will have their ASPD reduced and receive Corrosion Damage "build-up" periodically and when attacked, which, as with Nervous Impairment in Under Tides, does not do anything on its own but will cause negative effects should the Corrosion Damage reaches a certain threshold. If one haven't noticed it, the Hounds also takes damage and move and attack slower while wading through tiles submerged by the High Tide. Erosion also affects enemies, but works somewhat differently than on friendlies; it reduces their ASPD and speed, and causes them to lose HP over time instead.
Right as three additional Hounds spawn from F11, Bubble's Corrosion Damage meter is depleted, resulting in her receiving some damage and had her DEF lowered; should a friendly unit's Corrosion Damage reaches 1000, they will receive 800 Physical damage and have their DEF permanently reduced by 100 (which stacks additively if the Corrosion Damage procs on one friendly multiple times). While Corrosion Damage is not as debilitating as Nervous Impairment, low-HP/low-DEF Operators hurts the most from Corrosion Damage while those with high-HP/high-DEF aren't affected as much but could potentially have paper-thin defenses if left unchecked. As such, exercise caution in DH operations to avoid such situations, especially since aside of certain Stickers and Wandering Medics who can remove Elemental Damages including Corrosion Damage (which are not yet released in the Global server by the time DH is released), there are no ways to remove Corrosion Damage.
Aciddrop is quickly deployed on G7 facing down to eliminate the Hounds, and shortly after, the High Tide recedes and the melee tiles are no longer submerged, allowing deployment of units. Gavial is then deployed just before another High Tide starts, but this time with a number of Delinquents joining the party. At this moment, Beagle, Jessica, and May are available for deployment; deploy Jessica and May on B4 and B5, respectively facing right, who will be able to pick off the Delinquents heading to C3. The Delinquents, however, are capable of dodging Physical attacks when not blocked, but luckily, the High Tide recedes after a while; use this moment to deploy Beagle on C5 to block the Delinquents and making them easier targets for Jessica and May.