Using an array as argument for string.Format()

Quick fix.

var place = new object[] { 1, 2, 3, 4 };

C# does not support co-variant array conversion from int[] to object[] therefor whole array is considered as object, hence this overload with a single parameter is called.

It is possible to pass an explicit array for a params argument, but it has to have the matching type. string.Format has a few overloads, of which the following two are interesting to us:

string.Format(string, params object[])
string.Format(string, object)

In your case treating the int[] as object is the only conversion that works, since an int[] cannot be implicitly (or explicitly) converted to object[], so string.Format sees four placeholders, but only a single argument. You'd have to declare your array of the correct type

var place = new object[] {1,2,3,4};

You can convert int array to string array as pass it using System.Linq Select() extension method.

infoText.text = string.Format("Player1: {0} \nPlayer2: {1} \nPlayer3: {2} \nPlayer4: {3}", 
                              place.Select(x => x.ToString()).ToArray());

Edit:

In C# 6 and above, you can also able to use String Interpolation instead of using string.Format()

infoText.text = $"Player1: {place[0]}\nPlayer2: {place[1]} \nPlayer3: {place[2]} \nPlayer4: {place[3]}";

Check this fiddle for your reference.