The Mind Shield helps prevent aliens from finding your base, thus lessening the need for other Base Defence Systems. Once an alien group finds your base, they will continue to attack that base until you allow them to land, then defeat them in tactical combat.
It will not prevent races who already know your location from attacking you, but will rather lessen the chances of them finding you in the first place.
Construction Time: 33 days
Construction Cost: $1,300,000
Maintenance Cost: $5,000/month