Тимур Покровский

using System;
using System.Diagnostics;

namespace ConsoleApp19 {
	class Program {
		struct Cell {
			public string type;
			public string player;
			public bool isUnit;
		}

		public static void Main() {
			const int size = 1_000;

			object[,,] objs = new object[size, size, 3];
			Cell[,] cells = new Cell[size, size];

			Stopwatch timer = new Stopwatch();
			timer.Start();
			for (int i = 0; i < size; i++) {
				for (int j = 0; j < size; j++) {
					objs[i, j, 0] = "type";
					objs[i, j, 1] = "player";
					objs[i, j, 2] = false;

					string type = (string)objs[i, j, 0];
					string player = (string)objs[i, j, 1];
					bool isUnit = (bool)objs[i, j, 2];
				}
			}
			timer.Stop();
			Console.WriteLine(timer.ElapsedMilliseconds);

			timer.Reset();
			timer.Start();
			for (int i = 0; i < size; i++) {
				for (int j = 0; j < size; j++) {
					cells[i, j].type = "type";
					cells[i, j].player = "player";
					cells[i, j].isUnit = false;

					string type = cells[i, j].type;
					string player = cells[i, j].player;
					bool isUnit = cells[i, j].isUnit;
				}
			}
			timer.Stop();
			Console.WriteLine(timer.ElapsedMilliseconds);
		}
	}
}