What is wrong with my Invader classes/interface?

public MapLocation Location => _incarnation1.isNeutralized ? _incarnation2.Location : _incarnation1.Location;

public bool HasScored => _incarnation1.HasScored || _incarnation2.HasScored;

public int Health => _incarnation1.isNeutralized ? _incarnation2.Health : _incarnation1.Health;

public bool IsNeutralized => _incarnation1.IsNeutralized && _incarnation2.IsNeutralized;

public bool IsActive => !(IsNeutralized || HasScored);

public ResurrectingInvader(Path path)
{
  _incarnation1 = new BasicInvader(path);
  _incarnation2 = new StrongInvader(path);
}

public void Move()
{
  _incarnation1.Move();
  _incarnation2.Move();
}

public void DecreaseHealth(int factor)
{
  if(!_incarnation1.IsNeutralized)
  {
    _incarnation1.DecreaseHealth(factor);
  }
  else
  {
    _incarnation2.DecreaseHealth(factor);
  }
}

protected virtual int StepSize { get; } = 1;

// Properties over accessor methods
public MapLocation Location => _path.GetLocationAt(_pathStep);

public abstract int Health { get; protected set; }

// True if the invader has reached the end of the path
public bool HasScored { get { return _pathStep >= _path.Length; } }

public bool IsNeutralized => Health <= 0;

public bool IsActive => !(IsNeutralized || HasScored);

// Constructor
public Invader(Path path)
{
  _path = path;
}

public void Move() => _pathStep += StepSize;

public virtual void DecreaseHealth(int factor)
{
   Health -= factor;
   System.Console.WriteLine("Shot at and hit an invader!");
}

int Health { get; }

bool IsNeutralized { get; }

bool IsActive { get; }

void DecreaseHealth(int factor);

        try 
        {
          Path path = new Path(
           new [] {
              new MapLocation(0, 2, map),
              new MapLocation(1, 2, map),
              new MapLocation(2, 2, map),
              new MapLocation(3, 2, map),
              new MapLocation(4, 2, map),
              new MapLocation(5, 2, map),
              new MapLocation(6, 2, map),
              new MapLocation(7, 2, map)
            }
          );

          IInvader[] invaders = 
          {
            new ShieldedInvader(path),
            new FastInvader(path),
            new StrongInvader(path),
            new BasicInvader(path),
            new ResurrectingInvader(path)
          };

          Tower[] towers = {
             new Tower(new MapLocation(1,3,map)),
             new StrongTower(new MapLocation(3,3,map)),
             new LongRangeTower(new MapLocation(5,3,map)),
          };

          Level level = new Level(invaders)
          {
            Towers = towers
          };

          bool playerWon = level.Play();

          Console.WriteLine("Player " + (playerWon ? "won" : "lost"));

        }
        catch(OutOfBoundsException ex)
        {
          Console.WriteLine(ex.Message);
        }
        catch(TreehouseDefenseException)
        {
          Console.WriteLine("Unhandled TreehouseDefense Exception");
        }
        catch(Exception ex)
        {
          Console.WriteLine("Unhandled Exception: " + ex);
        }
    }
}