[Drixevel]

public Action:Event_Round_Start(Handle:event, const String:name[], bool:dontBroadcast)
{
	for (new i = 1; i <= MaxClients; i++)
	{
		if(IsClientInGame(i) && IsPlayerAlive(i))
		{
			SetEntProp(i, Prop_Data, "m_takedamage", 0, 1);
		}
	}
	
	CreateTimer(60.0, GodOff);
}

public Action:GodOff(Handle:timer)
{
	for(new i = 1; i <= MaxClients; i++)
	{
		SetEntProp(i, Prop_Data, "m_takedamage", 2, 1);
	}
	
	CreateTimer(90.0, GiveBeacon);
}

public Action:GiveBeacon(Handle:timer)
{
	ServerCommand("sm_beacon @all");
	
	CreateTimer(90.0, blabla...);
}

Not sure what you're trying to do but that's what I see.