This bsp + vmf includes a simple 1+1=2=Trigger system. It also provides examples of triggers, sounds, lighting and lightmaps.
**The mathcounter starts on one. Button 1 adds one to the mathcounter. Button 2 adds one to the mathcounter. The mathcounter is on 3 and the max is 3. When its on max it have triggered a door to break and spawn a zombie. **






