Tech tree.

[Taraea]

Here's a quickie tech tree guide. Note that for the Barrier cannon, upgrading either Left or Right allows access to Up or Down.


Heavy I
-Heavy II
--Heavy III -> Heavy IV
--Missile Launcher -> Missile Launcher II
-Impact I
--Impact II -> Impact III
--Ice -> Ice II
-Double Heavy I
--Sonic Pulse I -> Sonic Pulse II

Quick I
-Quick II
--Quick III -> Quick IV
--Flame Thrower I -> Flame Thrower II
-Sniper I
--Sniper II -> Sniper III
--Laser I -> Laser II
-Long Range I
--Long Range II -> Long Range III
--Electric I -> Electric II

Double I
-Double II
--Double III -> Double IV
--Boomerang I -> Boomerang II
--Barrier Down
---Barrier Left
---Barrier Right
----Barrier Up
----Barrier Down
-Double Quick I
--Double Quick II -> Double Quick III
--Machine Gun I -> Machine Gun II
-Triple I
--Triple II -> Triple III
--Poison Spray I -> Poison Spray II