The _token and _method fields are automatically added to all forms in Laravel as a security measure to prevent cross-site request forgery (CSRF) attacks. To allow mass assignment of these fields, you need to add them to the fillable property in your model.
To fix the error, update your Game model to include _token and _method in the fillable property:
class Game extends Model
{
use HasFactory;
protected $fillable = ['name', 'altname', 'system', '_token', '_method'];
}
This will allow Laravel to mass assign the _token and _method fields when updating the Game model.
Note that you should only add fields to the fillable property if you trust the source of the data. If you're accepting user input, you should validate the input first to ensure that it's safe to mass assign.