Imminent Incursion is the tower defense mini-game in Arknights: Endfield, which can be accessed early on for some extra Stock Bill generation. This guide will provide you with tips and tricks on how to succeed in this tower defense game, including all the combat towers and best strategies.
How Imminent Incursion Works
This mode tasks you with defending Command Cores from waves of enemies using Combat AIC towers that function like automated turrets that can be built via your base’s AIC system. It unlocks after completing the “Defense Construction” side quest at the Refugee Camp, which is your first outpost, where you must reach at least Level 2 via prosperity from trades and completing OD Project: Refugee Camp I.
Once unlocked, you need to travel to an outpost with the red Imminent Incursion icon and interact with the Early Warning Terminal. Then, choose your risk level and one of the two modes available:
- Operator Intervention. Allows you to fight manually with operators alongside turrets, which can be considered as an easy mode.
- Auto-Defense. This one uses turrets only with no intervention, and it can be unlocked after clearing an Intervention, which is a hard mode.
If you’ve chosen the intervention scenario, then deploy Relay Towers and Electric Pylons for power from Sub-PAC or main AIC. Place your turrets in slots and start dealing with waves of enemies to keep the Command Cores intact.
List of All Combat Towers
| Towers | Types | Effects |
|---|---|---|
| Gun Tower | Physical | Basic rapid fire against mobs. |
| Heavy Gun Tower | Physical | Faster fire and empowered shots against elites. |
| Sentry Tower | Physical | Long range tower that prioritizes high threat sniping. |
| Grenade Tower | Heat | AoE ballistic explosions at intersections. |
| H.E. Grenade Tower (Wuling) | Heat | AoE and burning ground on paths. |
| Beam Tower | Electric | High single-target beam against tanks. |
| Surge Tower | Electric | Arcs chain to clumped nearby foes. |
| Marsh Gas Mk I (Wuling) | Nature | AoE and slowing mist. |
| LN Tower | None | AoE slow on shatter that stalls enemies for DPS ramp. |
| Omnidirectional Sonic | None | AoE stun on commons and advanced foes for control. |
| Medical Tower | None | Supporter tower that heals your operators. |
Best Tower Defense Strategy
If you have experience with other tower defense games, then it’ll be easier for you to get into the rhythm of the Imminent Incursion. Here’s how you need to proceed:
- Spread along full paths for chip damage and avoid clumps at one spot.
- Overlap at bends and intersections for AoE efficiency.
- Create special corridors for some extra DPS and stun possibilities.
- Prioritize stuns at choke points for raw DPS and use Surge and Beam towers for damage spikes.
- Drag your power relays far if needed and ensure full coverage.
- Scout waves beforehand and counter elites in the first place.
It’s also highly recommended to unlock Advanced Tower Upgrade Paths, which is a tech tree accessed via the AIC interface. It unlocks nodes for combat blueprints, progressing from Basic Plan tiers to region-specific ones like Wuling. Don’t prioritize this in the early game, but they’ll be super useful in the later stages when you face harder threats. Here’s what you need to do:
- Collect AIC Index from Protocol Dataloggers, which are shown as inflatable tube men on the map.
- Enter AIC Plan and spend your Index on these nodes.
- Use VR Simulators to teach nodes and earn a bonus Index.
