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Field guide Roster I-400 Sen-Toku

The sneaky striker — long reach, must surface to shoot

I-400 Sen-Toku

Toughest water HP, slowest, tiny magazine, huge 7.2-tile missile/torpedo reach. Claims water, threatens anything from the coast — but every missile surfaces the boat and invites anti-air.

At a glance

Where it goes
Water — two population, heavy
Health / Speed / Magazine
250 HP / slow / 4 shots before a long reload cycle
Gun
Heavy torpedo vs subs, heavy missile vs everything else — soft vs buildings/HQ by design
Stealth
Submerged it still scouts about 8.0 tiles and is almost invisible; revealed for a short window after surfacing or Radar

I-400 submarine

I-400 subs strike from long range but must surface to fire, briefly revealing them to Radar. Four torpedoes before you need to rearm.

By the numbers

An I-400 hits like a truck — per shot it's the hardest in the roster — but it cycles slowly. Against land and especially against HQs and buildings, its missiles are deliberately softened so four subs can't erase an HQ from offshore in seconds; they need the better part of a minute uncontested. Torpedoes vs other subs are full power.

Sub shoots atHow it feels
HQ (1,800 HP)Plink — four subs need about a minute
Support building (620 HP)Plink — still a long siege
Maus (400 HP)Heavy — about fourteen seconds solo
Sea Shadow (180 HP)Heavy — about half that

How to use it

Creep along the waterline offshore near the enemy HQ, focus the HQ, fire, and move — every missile surfaces you and anti-air will answer. A submerged I-400 is great at sitting still on a buoy or a quiet coast and waiting, then popping up to shoot and sliding. Don't knife-fight without Radar.

The Pen

A Sub Pen is a coastal dock that quietly auto-launches a new I-400 about every 30 seconds for modest supply, up to four. It's not a queue — when the timer hits zero and you have the supply and population, a new boat just slides into the water and logs it.

Buoys are your buoy

Only subs can flip sonar buoys. A Sea Shadow on a buoy does nothing for capture, but it can kill the enemy sub that is flipping it. Pair subs with boats: subs flip, boats screen.