The yellow star means the unit is upgraded
$30M, 60M RP
Shield is the upgrade for the Nod unit Cobra and it is useful against anti-aircraft vehicles and passing through infantry or some anti-aircraft structures without much trouble. It can be enhanced in the Offensive Tab of the Research Menu. The cost of this upgrade is 30,000,000 of cash and 60,000,000 of Research Points. This feature is worthwhile to mid-level players.
The shield does not count in to the hit points of the unit, so if the shield is damaged, no attack damage will be reduced as long as the hit points of the shielded units are at 100%. Once the Shield is destroyed, the Cobra will lose hit points while under attack.
It is recommended that shielded Cobra should attack along with Venoms. So if you want to attack a well-defended Forgotten base, you should place the Venom in the right slot for enemy anti-aircraft infantries and Cobra, in the right slot for attack anti-aircraft vehicles or place them in the remained slots in some division, depending on the cases. However, the player must take care of Flaks.
In the Research panel, the upgrade name can be shown as Unit Special instead of Shield as called in the official post of the game which it introduces the new units upgrades for the last patch.