DIYGamer: The tower defense genre is a rather crowded market at the moment. Most would trace the history of such games back to a particularly addictive Warcraft 3 mod, and most will make the mistake of lumping Robot Entertainment’s multiplatform title Orcs Must Die! in as part of that comparatively recent offshoot. In reality, OMD draws most of its strengths from much more venerable stock, blending the gameplay of 1994′s The Horde and Tecmo’s Deception series. But do the charms of those mid-90s hits hold up in the year 2011? Read on and all will be answered – just mind the spike trap under the doormat.