TL;DR: I think Kamikaze tokens are worth about 4-5 IPCs each to Japan.
@AlphaKappa I would defer to people with more experience, but Kamikazes have two concrete or ‘hard’ purposes and at least one ‘soft’ purpose.
1. [Hard] Sink valuable ships
With their target select feature, Kamikazes can hit large ships directly and ignore cannon fodder like destroyers and subs. (or maybe sink a couple key destroyers to allow subs to dodge planes and surprise strike a now-exposed fleet).
In the simplest sense, there are some 6 scenarios for Kamikaze hit values:
– Destroyer (8 IPC)
– 1/2 Carrier; No lost fighters (8 IPC)
– 1/2 Battleship (10 IPC)
– Cruiser (12 IPC)
– 1/2 Carrier causing 1/2 sunk Fighter (16/2 + 10/2 = 13 IPC)
– 1/2 Carrier causing 1 sunk Fighter (16/2 + 10 = 18 IPC)
– 1/2 Carrier causing 2 sunk Fighters (!!) (16/2 + 20 = 28 IPC)
Calculating the average value here could be as simple as figuring out the expected damage per Kamikaze roll with an equation like $Kavg = %h x $Tavg, where %h = 1/3 (Kamikazes hit on a 2) and the $Tavg = ~12 (trying to place this near the 'center of gravity for hit scenarios) . So with those numbers, the average value of a Kamikaze is about 4 IPC.
Of course, you’d probably want assurance you’re going to sink those targets and not simply allocate one Kamikaze per expected hit. This pushes the value of Kamikazes down considerably, since you can’t wait to see if they were effective before sending out the next wave. The laws of RNG say that you’re bound to overallocate in some cases and underallocate in others.
Finally, this assumes that these targets would even present themselves in the relevant Sea Zones. However, this objection can be resolved by qualifying the question to be: How much is a Kamikaze worth assuming that valid uses present themselves?
I would gloss, then, that for this purpose
ship-sinking Kamikaze tokens are worth between 3-4 IPC each.
2. [Hard] Prevent Bombardment during Amphibious Landings
A single Kamikaze token can prevent all naval bombardment from a given SZ during amphibious invasion. Figuring the value in this use case is speculative and situational, but we can try with some big assumptions:
Lets assume that the targets for bombardment are always infantry units, so a successful bombard hit is going to cost Japan 3 IPCs.
Because most contested amphibious invasions land at least 4 units with bombardment support increasingly likely in the mid-endgame where Kamikaze could happen, lets broadly assume that the average number of prevented bombard shots in a Kamikaze-contested landing is 3, and that those shots are going to be taken by 2 battleships and 1 Cruiser.
With these assumptions and the simplest setup, we can roughly guess that A kamikaze token used this way is worth $Kavg = Bh x $Tb, where BHavg = 1 5/6 (the average prevented bombardment hits = 0.66 + 0.66 + 0.5) and $Tb = 3 IPC (the cost of each prevented infantry hit), for a total savings of 5.5 IPCs worth of Infantry units.
The real impact of the Kamikaze in the case, however, would be how much extra the attacking player has to bring to account for the lost bombardment. In this case, that’s probably close to the expected damage that those three saved infantry are going to inflict on his landing force, which for a single round of combat against a far-superior landing force is about 3 IPC (0.33 hit chance/inf x 3 infantry); in a much closer battle (in which case, why are you invading in the first place?) lasting multiple rounds the impact could be closer to 6 or even the full 9. Let’s say then that our impact to the attacker is somewhere between 3 and 6 IPCs.
But finally, the spent Kamikaze token might actually hit something! If we go after a cruiser, say, then using the equation from 1. above gives an additional average value of 4 IPC (12 IPC cruiser sunk x 1/3 of the time).
This would give the average bombardment-preventing Kamikaze token a conservative value of 4 + 3 = 7 IPC, varying wildly by situation.
3. [Soft] Deter Naval Incursions
With at least the potential to sink 6 escort ships in one go, Kamikazes have a fun ‘soft’ threat value in the game. It’s unlikely to come off that way, of course, and the threat dissipates with each spend token as the game goes on, but it’s at least possible that one single massive Kamikaze strike could net the Japanese player an incredible 72 IPC of impact or 12 IPC per token. This would be enough to swing a majority of endgame naval confrontations, and has to at least be accounted for by the US player if mounting a KJF.
If I were the US and wanted to conservatively plan around a massive endgame kamikaze strike, I would plan to take fully three hits and so overbudget for that attack by at least 36 IPC.
So
for the purpose of deterring an endgame naval incursion, I would give Kamikaze tokens a value of 6 IPC each.
All of this asks what they’re worth, not what I would pay as Japan where resources are precious and actual units are worth much more than mere potentialities.
While my equations yield a value of around 6, I would personally probably only pay 4-5.