Strategy Informer  

RA3: Trinity Defense or just R3D features the Tower Defense mode in which you must survive the tides of Creeps with just your towers or superweapons. For this job you have a variety of new zany base defenses under your command, not just the ones known from Red Alert 3. While being mostly developed for Multiplayer together with others, R3D also supports Singleplayer adjustments and many options which alltogether define the difficulty outcome.

You may want to play the beta v1.0 for a first impression.