Shurikens can store 4 stun charges, with charges recharging at 40% firing rate.
Optional: Add smart targeting that prevents shuriken from wasting shots via overstunning.
This lets shuriken have a strong initial stun, but maintains urgency for allies to respond to the leak immediately, and makes it difficult for them to lock down aa permanently.
The Problem
Shuriken deny almost all leaks early game, making the raiding game stale.
-Shuriken travel extremely fast, have high stun power. They can be made in response to a leak and still arrive in time
-Shuriken's high speed allows them to retreat vs enemy figs. Since figs are extremely fragile versus aa, figs can be dissuaded from chasing shuri's.
-Shuirken's weakness is that they actually require allied units to come clean up the unit. However this is not a problem since shuriken can keep the unit stunned forever. 1 shuriken can technically keep a tzar stunned permanently.
To preserve their ability to contribute to the game, air labs could get buffs in compensation like:
Both: More scout HP, less bp on air cons
Cor: Add gunship
Arm: more scout LOS, better gunship