Welcome to the monastery iraid3r

Anonym pointend you about the fact that $enem is not an object, but maybe this is good for you: if i understand your question correctly you create an object-sprite and want to reuse for many anonymous hashes like $enem (so $enem and company will be not objects).

In this case you have a lot of options: if you isolate,for example, coordinates for the creation of the army into an ArrayofArrays where each element is a pair of x and y. like  @coord_pairs = ( [1,2], [3,7], [5,9]) then you can cycle through them as in:

my @coord_pairs = ( [1,2], [3,7], [5,9]);
my @enemy_container;

foreach my $index (coord_pairs) {
   
   my $enem = {
    sprite => $enemy_sprite ,
    v_y    =>  $coord_pairs[$index]->[0], # element 0 of the current p
+air
    v_x    =>  $coord_pairs[$index]->[1], # element 1 of the current p
+air
    };

   push @enemy_container, $enem;
}
[download]

As said there a lot of options to deal with lists and arrays: foreach while map shift pop ...

i know nothing about SDL, and dunno if you can reuse the created sprite seveveral times: maybe you need to clone it, or in the worst case you can create a new sprite for each enemy created, even if the png is the same:

my @coord_pairs = ( [1,2], [3,7], [5,9]);
my @enemy_container;

foreach my $index (coord_pairs) {
   
   
   my $temp_enemy_sprite = SDLx::Sprite->new ( width => $20, height =>
+ $20 );
   $enemy_sprite->load('example.png');

   my $enem = {
    sprite => $temp_enemy_sprite ,
    v_y    =>  $coord_pairs[$index]->[0], # element 0 of the current p
+air
    v_x    =>  $coord_pairs[$index]->[1], # element 1 of the current p
+air
    };

   push @enemy_container, $enem;
}
[download]

As little side note, avoid name like $20 for your variables: if you are starting coding choice meaningful name for them as i tried to do in my little example. There is chance to other parts of the program change the value (accidentally) of $20 ending with $20 containing 30. Perl let you to define true constant as described in the docs. In this case you can use constant TWENTY => 20; because number are not allowed as constant name (but you can use _20).

Post clear question to obtain the best from perlmonks. i'm courious to see your gaming attempt anyway.

HtH
L*