Plasma Cannon

The Plasma Cannon is the strongest defensive weapon in SFC2. It hits for 3,000, carries 10,000 hull, and nothing in the game has rapid fire against it. It is also the most expensive thing you can park on a planet, so it pays to know where it earns its keep.

You build it on the Defense page. The planet needs a Shipyard at level 8 and Plasma Tech at level 7.

Statistics

	Base	At tech 14
Attack Strength	3,000	7,200
Shield Strength	300	720
Hull	10,000	24,000

Weapons Tech, Shield Tech and Armor Tech each add 10 percent of the base figure per level, and they cover defenses exactly the way they cover ships. The bonus is flat, not compounding, so level 14 is base plus 140 percent. The Current column on the Defense page is what you actually fight with.

Nothing rapid fires it

Rapid fire lets an attacking ship take another shot the moment it lands on a soft target, and the chain keeps rolling until a shot lands on something with no rapid fire behind it. A Zeus rapid fires the Missile Battery and the Laser Cannon at 200, the Pulse and Particle Cannons at 100, and the Gauss Cannon at 50. On a rating of 50 it keeps firing 49 times out of 50, so one Zeus that lands in a wall of Gauss Cannons averages about fifty shots before it stops.

The Plasma Cannon, the Decoy and the Large Decoy are the only defenses nothing rapid fires. A shot that lands on one of them ends the chain. The Zeus still kills the cannon it hits, since 200,000 attack goes straight through 10,000 hull, but it only gets the one shot for it.

What one shot kills

A plasma shot is 3,000 damage with no tech on either side. Shields come off first and reset at the start of every round, while hull damage carries over. At the end of a round, anything that has lost more than 30 percent of its hull rolls to explode, and the chance is the same as the share of hull it has lost.

Target	Hull	Result of one plasma shot
Hermes Probe, Shadow Probe	100	destroyed
Helios and Genesis satellites	200	destroyed
Artemis Fighter, Atlas Cargo	400	destroyed
Zagreus Recycler	800	destroyed
Apollo Fighter	850	destroyed
Hercules Cargo	1,200	destroyed
Dionysus Recycler	1,600	destroyed
Poseidon Cruiser	2,700	destroyed
Gaia Colony Ship	3,000	100 hull left, 97 percent chance it blows up
Carmanor Cargo	3,600	700 hull left, 81 percent chance it blows up
Athena Battleship	6,000	3,200 hull left, 47 percent chance it blows up
Hades Battleship	7,000	4,400 hull left, 37 percent chance it blows up
Ares Bomber	7,500	5,000 hull left, 33 percent chance it blows up
Prometheus Destroyer	11,000	8,500 hull left, no explosion roll

So the old claim that a Plasma Cannon drops an Athena in one shot is about half right. The damage on its own does not do it. The explosion roll does, and it comes up a bit under half the time. Armor Tech on the fleet pushes every one of those percentages down, and Weapons Tech on your side pushes them back up.

It needs cheap hulls in front of it

Targeting in a battle is random. Every shot the attacker fires picks one defender out of everything you have, so a wall made only of Plasma Cannons takes the whole fleet on the chin and is gone in two rounds. Put the same money into cheap hulls with a few cannons mixed in and the cannons live all six rounds and fire six times.

Here is the same 2,600,000 resource budget spent five different ways, against 150 Athenas and 50 Hades, with weapons, shield and armor at 8 on both sides. Twenty five runs of the battle engine each.

Defense	Planet held	Attacker resources killed
1,300 Missile Battery	25 of 25	65,000
5 Plasma, 975 Missile Battery	25 of 25	1,229,000
10 Plasma, 650 Missile Battery	3 of 25	1,917,000
15 Plasma, 325 Missile Battery	0 of 25	1,888,000
20 Plasma	0 of 25	684,000

A pure fodder wall survives everything and kills almost nothing. A pure plasma wall dies fast and, because it was gone by round three, kills less than the mix does. Five cannons behind a thousand batteries held the planet every single time and still ate more than a million resources of the attacking fleet, and lost less than one cannon per attack doing it.

That is the five cannon wall in the Calculator. Six rounds, no winner, so the attacker goes home with no plunder and 1,405,000 resources of dead ships. The debris line is all attacker ships. Defenses never leave any.

After the battle

Roughly 70 percent of every defense you lose is rebuilt for free the moment the battle ends, so a wall you paid for once keeps working for a long time. The report shows what came back.

Two more things work in your favour. Dead defenses leave no debris, so nobody recycles your cannons back into their own economy. And destroyed defenses are worth zero rank points, so a raider who flattens your wall gets nothing for it on the leaderboard.

Missiles are the real threat

An Interplanetary Ballistic Missile does 12,000 damage, raised 10 percent per level of the attacker's Weapons Tech, and shields do nothing against it. A Plasma Cannon has 10,000 hull, so at base one missile is one dead cannon. Your Armor Tech is the only thing that changes that. At Armor 10 the cannon carries 20,000 hull and it takes two missiles.

Missiles chew through your cheapest defenses first, and the Plasma Cannon is the most expensive item on the Defense page, so it normally sits at the back of the line. An attacker who wants your cannons specifically has to name them as the priority target when the strike is launched. Nothing a missile kills regenerates, and Anti-Ballistic Missiles are the only counter.

Cost

Ore	Crystal	Hydrogen
50,000	50,000	30,000

That is 130,000 resources a cannon, against 37,000 for a Gauss Cannon and 2,000 for a Missile Battery.

Requirements

Shipyard (level 8)
Plasma Tech (level 7)

More Info on the Defense page lists both, along with the rapid fire line.

Build time

Build time comes off the Shipyard level and then halves with every level of the Foundry. One cannon:

Shipyard	Foundry	Time
8	0	2h 13m
8	2	33m
10	4	6m 49s
12	6	1m 26s
14	8	18s

Things worth knowing

Defenses share the Shipyard queue with ships. A batch of cannons blocks ship production until it finishes.
You cannot start a defense while the Shipyard or the Foundry is upgrading.
Once a cannon is built it stays where it is. There is no way to take it down, sell it or move it. Missiles are the only defense you can deconstruct.
A moon cannot build a Shipyard, so it cannot hold defenses of any kind. Neither can a Hephaestus platform.
Anyone who scouts you with enough Espionage Tech sees your cannons listed by name and count before they commit a fleet.