Firstly, you're oversimplifying. Secondly, I didn't quite understand how you envision the "blender" process. If the idea is to give it all the abilities in the game... then I think that's a very bad idea.
Of course, that would create a creature that could guaranteed win any argument against "the tough guy from next door." And finally settle the debate of "who is stronger, Jackie Chan, Schwarzenegger, or Spider-Man." But again, are we five years old? Why create an invincible creature?
Was that too subtle? It was sarcasm, you know.)
But seriously, the first thing that comes to mind in terms of abilities is splash or devastating strike, since the creature has many limbs and is large. Perhaps infinite retaliation + battle frenzy, or infinite retaliation + ferocious retribution would also work well. Also, resistance to dark magic is a must-have.
Among the more or less suitable abilities, there's also deadly strike, terrible neighborhood (an unbalanced ability, but perfect for a boss), bash, and magic strike.
I wouldn't give the boss spells; it just doesn't seem to fit with this creature's theme of magic.
As for stats, we need to base them on the set of abilities...
[Модификация]Phoenix Vision - Комплексное модифицирование визуального аспекта игры.
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[Модификация]VisualFix-Устрание визуальных багов.
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