Major_Project_A/Assets/Scripts/Logic/Blocks/Replace.cs

using System.Collections;
using UnityEngine;

[CreateAssetMenu(menuName = "Major Project/Pick Ups/Replace Block")]
[System.Serializable]
public class Replace : LogicBlock
{
    public GameObject blockPrefab;

    public override Block GetEndBlock(Block startBlock, Transform transform, LayerMask layerMask)
    {
        return startBlock;
    }

    protected override IEnumerator BlockLogic(Character player, float animationTime, bool useBlockDirection = false)
    {
        Block oldBlock = player.CurrentBlock;
        Transform parent = oldBlock.transform.parent;
        Vector3 position = oldBlock.position;

        Block newBlock = Instantiate(blockPrefab, parent).GetComponent<Block>();
        newBlock.transform.position = position;

        yield return player.StartCoroutine(player.MoveToBlock(newBlock, Character.Animation.None, 0.0f));
        Destroy(oldBlock);
    }

    public override void CopyToken(BlockToken token)
    {
        base.CopyToken(token);
        blockPrefab= Resources.Load<GameObject>(((ReplaceToken)token).prefabName);
    }

    public override BlockToken ToToken(BlockToken token = null)
    {
        if (token == null)
            token = new ReplaceToken(this);

        Debug.Log(base.ToToken(token).GetType().Name);
        ReplaceToken retVal = (ReplaceToken)base.ToToken(token);
        retVal.prefabName = blockPrefab.name;

        return retVal;
    }
}

[System.Serializable]
public class ReplaceToken : BlockToken
{
    public string prefabName;
    public ReplaceToken(LogicBlock block) : base(block) { }
}