BoidBase.cs

namespace Assets.RED.Scripts.Behaviors
{
	using System;
	using UnityEngine;
	
	public abstract class BoidBase : MonoBehaviour
	{
		public float DetectionRadius;

		public float TurningSpeed;

		public float Velocity;
	}
}

FlockCenter.cs

namespace Assets.RED.Scripts.Behaviors
{
	using System;
	using System.Linq;
	using UnityEngine;

	public class FlockCenter : BoidBase
	{
		private void FixedUpdate()
		{
			// Find all the objects within the boid's detection radius.
			var scanHits = Physics.OverlapSphere(base.transform.position, base.DetectionRadius);

			int count = 0;
			Vector3 sum = new Vector3 ();

			// Iterate over all objects and if they're of the same type the move towards center of the flock
			foreach (var hit in scanHits.Where(h => h.collider.tag == "Enemy"))
			{
				sum = sum + hit.collider.rigidbody.position;
				count++;
			}

			var center = sum / count;
			var desiredPosition = center.normalized;
			base.transform.position = Vector3.MoveTowards (base.transform.position, desiredPosition, Time.deltaTime);
			base.rigidbody.velocity = base.transform.TransformDirection(Vector3.forward * base.Velocity);
		}
	}
}