unhack that a bit; delayed damage works

OpenRA.Game/Combat.cs

@@ -69,6 +69,19 @@ namespace OpenRA
 					(int)GetDamageToInflict(victim, args, warhead, firepowerModifier), warhead);
 		}
 
+		public static void DoImpacts(ProjectileArgs args, int2 visualLocation)
+		{
+			foreach (var warhead in args.weapon.Warheads)
+			{
+				Action a = () => DoImpact(warhead, args, visualLocation);
+				if (warhead.Delay > 0)
+					args.firedBy.World.AddFrameEndTask(
+						w => w.Add(new DelayedAction(warhead.Delay, a)));
+				else
+					a();
+			}
+		}
+
 		static float GetMaximumSpread(WeaponInfo weapon, WarheadInfo warhead, float modifier)
 		{
 			return (int)(warhead.Spread * Math.Log(Math.Abs(weapon.Damage * modifier), 2));

OpenRA.Game/Effects/Bullet.cs

@@ -78,11 +78,7 @@ namespace OpenRA.Effects
 		{
 			t += 40;
 
-			if (t > TotalTime())		/* remove finished bullets */
+			if (t > TotalTime()) Explode( world );
-			{
-				world.AddFrameEndTask(w => w.Remove(this));
-				Combat.DoImpact(Args.weapon.Warheads[0], Args, VisualDest - new int2(0, Args.destAltitude));
-			}
 
 			if (Info.Trail != null)
 			{
@@ -126,5 +122,11 @@ namespace OpenRA.Effects
 						Info.UnderWater ? "shadow" : Args.firedBy.Owner.Palette);
 			}
 		}
+
+		void Explode( World world )
+		{
+			world.AddFrameEndTask(w => w.Remove(this));
+			Combat.DoImpacts(Args, VisualDest - new int2(0, Args.destAltitude));
+		}
 	}
 }

OpenRA.Game/GameRules/WarheadInfo.cs

@@ -34,6 +34,7 @@ namespace OpenRA.GameRules
 		public readonly string ImpactSound = null;
 		public readonly string WaterImpactSound = null;
 		public readonly int Damage = 0;		// for new weapons infrastructure
+		public readonly int Delay = 0;		// delay in ticks before dealing the damage. 0=instant
 
 		public float EffectivenessAgainst(ArmorType at) { return Verses[ (int)at ]; }
 	}