diff --git a/src/environments/groupthm.pysty3 b/src/environments/groupthm.pysty3
index 13fef23..a84d141 100644
--- a/src/environments/groupthm.pysty3
+++ b/src/environments/groupthm.pysty3
@@ -11,6 +11,8 @@ __HEADER__(Grouping theorems for easier customization.)
 \hook_new:n { groupthm / mapname }
 \hook_new:n { groupthm / thmtools }
 
+\hook_new:n { groupthm / groupsort }
+
 
 \newcounter{indocument}
 \newcounter{insection}[section]
@@ -25,6 +27,7 @@ __HEADER__(Grouping theorems for easier customization.)
 }
 
 \cs_generate_variant:Nn \declaretheorem:nn { n V }
+\cs_generate_variant:Nn \hook_gset_rule:nnnn { n n V n }
 
 
 %%% Messages
@@ -56,6 +59,10 @@ __HEADER__(Grouping theorems for easier customization.)
 
 \tl_new:N    \l_groupthm_relation_tl
 
+\clist_new:N \l_groupthm_groups_clist
+
+\str_new:N   \g_groupthm_last_theorem_group_str
+
 
 %%% Keys
 
@@ -107,6 +114,12 @@ __HEADER__(Grouping theorems for easier customization.)
           \clist_put_right:Nn \l_groupthm_thmtools_clist { #5 }
         }
     }
+    \hook_gset_rule:nnnn { groupthm / groupsort }
+    \g_groupthm_last_theorem_group_str
+    { before }
+    {
+      #1
+    }
 }
 \cs_generate_variant:Nn \new_theorem_group:nnnnn { n V V V V }
 
@@ -150,6 +163,11 @@ __HEADER__(Grouping theorems for easier customization.)
 \cs_new:Npn \new_grouped_theorem:nnnn #1 #2 #3 #4
 {
   
+%  \tl_show:n { #1 }
+%  \tl_show:n { #2 }
+%  \tl_show:n { #3 }
+%  \tl_show:n { #4 }
+
   \tl_clear:N     \l_groupthm_prename_tl
   \tl_set:Nn      \l_groupthm_name_tl        { #3 }
   \tl_clear:N     \l_groupthm_postname_tl
@@ -183,6 +201,7 @@ __HEADER__(Grouping theorems for easier customization.)
     \l_groupthm_thmtools_clist
 }
 \cs_generate_variant:Nn \new_grouped_theorem:nnnn { n V V V }
+\cs_generate_variant:Nn \new_grouped_theorem:nnnn { x V n n }
 
 % envname, keys
 \cs_new:Npn \new_grouped_theorem_from_keys:nn #1 #2
@@ -215,6 +234,9 @@ __HEADER__(Grouping theorems for easier customization.)
 }
 
 
+
+%% Rules for different theorem groups
+
 \cs_generate_variant:Nn \hook_gset_rule:nnnn { n n V n }
 
 % hook group1 relation group2
@@ -241,6 +263,145 @@ __HEADER__(Grouping theorems for easier customization.)
   \declare_theorem_group_rule:nnnn {#1} {#2} {#3} {#4}
 }
 
+%%% Iterate over powerset of claist
+
+\clist_new:N \copied_clist
+\seq_new:N \saved_seq
+
+%remove left  -> push on stack
+% call recursive
+% add left to 'extra'
+% call recursive
+% remove left from 'extra'
+% add from stack to left
+
+
+\cs_generate_variant:Nn \clist_remove_all:Nn { N V }
+
+\cs_new:Npn \clist_use_powerset_aux:Nn #1 #2 
+{
+  \clist_if_empty:NTF \copied_clist
+    {
+      #2
+    }
+    {
+
+      \clist_get:NN \copied_clist \l_tmpa_tl % gets first element of copied list into local
+      \seq_push:NV \saved_seq \l_tmpa_tl     % pushes local value onto stack
+      \clist_pop:NN \copied_clist { \l_tmpa_tl } % removes from copied list
+
+      \clist_use_powerset_aux:Nn #1 {#2}
+      
+      \seq_get:NN \saved_seq \l_tmpa_tl
+      \clist_put_left:NV #1 \l_tmpa_tl
+
+      \clist_use_powerset_aux:Nn #1 {#2}
+
+      \seq_get:NN \saved_seq \l_tmpa_tl
+      \clist_remove_all:NV #1 \l_tmpa_tl
+      \clist_push:NV \copied_clist \l_tmpa_tl
+      \seq_pop:NN \saved_seq \l_tmpa_tl
+    }
+}
+
+\cs_new:Npn \clist_use_powerset:Nn #1 #2
+{
+  \clist_set_eq:NN \copied_clist #1
+  \clist_clear:N #1
+  \clist_remove_duplicates:N \copied_clist
+
+  \clist_use_powerset_aux:Nn #1 {#2}
+
+  \clist_set_eq:NN #1 \copied_clist
+}
+
+
+%%% Theorem variants declaration
+
+\ExplSyntaxOn
+
+
+\cs_new:Npn \add_to_sort_hook:n #1
+{
+  \hook_gput_code:nnn { groupthm / groupsort }
+  { #1 }
+  {
+    \clist_put_left:Nn \l_groupthm_groups_clist { #1 }
+  }
+}
+
+\cs_new:Npn \sort_group_names:
+{
+  \hook_gremove_code:nn { groupthm / groupsort  }{*}
+  \clist_map_function:NN \l_groupthm_groups_clist \add_to_sort_hook:n
+  \clist_clear:N \l_groupthm_groups_clist
+  \hook_use:n { groupthm / groupsort }
+}
+
+
+% evname, name, thmtools, star?
+\cs_new:Npn \declare_theorem_variants_aux:nnnn #1 #2 #3 #4
+{
+
+  \clist_set:Nn \l_groupthm_groups_clist { dagger, star }
+%  \clist_set:Nn \l_groupthm_thmtools_clist {#3}
+%  \IfBooleanT{#4}
+
+  % envname, groups, name, thmtools
+%  \clist_sort:Nn \l_groupthm_groups_clist
+%  {
+%    \str_compare:nNnTF { #1 } > { #2 }
+%    { \sort_return_swapped: }
+%    { \sort_return_same: }
+%  }
+
+  \clist_use_powerset:Nn \l_groupthm_groups_clist
+  {
+    \sort_group_names:
+    \new_grouped_theorem:xVnn
+      {__#1__groups_\clist_use:Nn \l_groupthm_groups_clist {_}}
+      \l_groupthm_groups_clist
+      { #2 }
+      { #3 }
+  }
+
+
+  \NewDocumentEnvironment{#1}{ !s !t+ }
+  {
+    \clist_clear:N \l_groupthm_groups_clist
+    \IfBooleanT{##2}
+    {
+      \clist_put_left:Nn \l_groupthm_groups_clist { dagger }
+    }
+    \IfBooleanT{##1}
+    {
+      \clist_put_left:Nn \l_groupthm_groups_clist { star   }
+    }
+    \sort_group_names:
+    \begin{__#1__groups_\clist_use:Nn \l_groupthm_groups_clist{_}}
+  }
+  {
+    \clist_clear:N \l_groupthm_groups_clist
+    \IfBooleanT{##1}
+    {
+      \clist_put_left:Nn \l_groupthm_groups_clist { star   }
+    }
+    \IfBooleanT{##2}
+    {
+      \clist_put_left:Nn \l_groupthm_groups_clist { dagger }
+    }
+    \sort_group_names:
+    \end{__#1__groups_\clist_use:Nn \l_groupthm_groups_clist{_}}
+  }
+
+}
+
+\DeclareDocumentCommand{\DeclareTheoremVariants}{mmmm}
+{
+  \declare_theorem_variants_aux:nnnn{#1}{#2}{#3}{#4}
+}
+
+
 
 %%% Default groups available
 
@@ -286,3 +447,5 @@ __HEADER__(Grouping theorems for easier customization.)
 \DeclareTheoremGroupRule { starred } { higher             } { small  }
 \DeclareTheoremGroupRule { starred } { higher             } { dagger }
 \DeclareTheoremGroupRule { starred } { higher             } { star   }
+
+\DeclareTheoremGroupRule { starred } { higher             } { starred}