Added lots of security using asserts.

src/Library/CreatureData/CreatureSpecies.cpp

@@ -1,11 +1,14 @@
 #include "CreatureSpecies.hpp"
+#include <Arbutils/Assert.hpp>
 
 using namespace CreatureLib::Library;
 
 CreatureSpecies::CreatureSpecies(uint16_t id, const ConstString& name, const SpeciesVariant* defaultVariant,
                                  float genderRatio, const ConstString& growthRate, uint8_t captureRate)
     : _name(name), _id(id), _genderRate(genderRatio), _growthRate(growthRate), _captureRate(captureRate),
-      _variants({{"default"_cnc, defaultVariant}}) {}
+      _variants({{"default"_cnc, defaultVariant}}) {
+    AssertNotNull(defaultVariant)
+}
 
 bool CreatureSpecies::HasVariant(const ConstString& name) const { return _variants.find(name) != _variants.end(); }