This mod from rgggclp allows you to summon creatures to fight with you.
Stalker - Clear Sky 1.5.05 - Summoner Mod 0.3
This mod enpowers you the ability of summoning creatures which could fight for you.
You could summon all types of mutant you have seen in CS.
In addition, it's also possible to summon the mutants which are cut by the develpoers in the original Stalker, such as burer and chimera.
In order to summon, you have to ensure there's at least one body part of a mutant such as "dog tail" in your inventory.
The summoning process will consume the mutant's body part which correspond to the type of mutant that you could summon.
Then go to the main menu by pressing ESC, and then press:
key 1 : This allows you to summon a group of mutants instantly, which consumes all the corpse ingredients in your inventory.
key 2 : This allows you to summon one of the weakest mutant, which consumes one corpse ingredient.
key s : This allows you to summon one of the strongest mutant, which consumes one corpse ingredient.
Each Type of creatures has diffent strength. The strength of the creatures you have summoned has something to do with your rank. For example, master has a much better chance to summon strongest creatures than novice.
The dead body of a mutant has a chance to spawn corpse ingredient which could be used for summoning, the probability is 50 percent. This rule only applies to the mutants respawned after you install this mod.
In addition, you could go to the bunker in Yantar and buy corpse ingredients from the scientist.
This mod also integrates the time acceleration function which lets time elapse more quickly. To enable or disable it, go to main menu and press key F1.
After installation, you don't need restart game to adapt this mod.