Upgrades

Upgrades in Alien Creeps consider both increasing towers/ support items effectiveness and upgrading tower level from here so it can be upgraded in any level, as towers are not unlocked in levels. There are 8 upgrade paths now. There are 4 for each tower type and 4 for Support Items- Reinforcements, Airstrike, Cryo Bomb & Fusion Cell

' Note: There were 6 upgrade paths before, 4 for towers and 2 for support items. '

Coins
Upgrades are bought with coins, which can be obtained by:


 * Completing Levels depending on Campaign, Veteran and Spec Ops


 * Enemies Killed by Heroes gives coins which is fixed for the creep


 * Beating Challenges gives coins according to Difficulty

Reinforcements
Reinforcement previous cost & research time is unknown.

Airstrike
Airstrike previous cost & research time is unknown.

Cryo Bomb
A fully Upgraded Bomb has -25s Cooldown, Freezes about 6s & slows by an unknown period more than 6s