This type of structure provides ways to defend or repair your base or fleet.

Card	Race(s)	Rarity	Cost
Antigrav Shield	RV	common	2
Antimatter Field	CA	common	2
Armored Growth	MT	elite	3
Dark Energy Field	CA	uncommon	2
Dimensional Link	RD	elite	3
Growth Spire	MT	uncommon	3
Nanobot Tower	RV	uncommon	2
Nebula Spire	XY	elite	2
Restoration Field	HU	common	3
Shield Generator	HU	common	2
Shield Spire	CC	elite	3
Support Spire	CC	common	2
Virus Barrier	TM	elite	2