Crossword Genius

There are many sides to this German and, ultimately, he can go berserk (9)

Ross

I believe the answer is:

undecagon

'there are many sides to this' is the definition.
(eleven-sided shape)

'german and ultimately he can go berserk' is the wordplay.
'german and' becomes 'und' ('and' in German).
'ultimately' indicates one should take the final letters.
'berserk' indicates an anagram (I've seen this in other clues).
The last letter of 'he' is 'e'.
'can'+'go'='cango'
'cango' with letters rearranged gives 'cagon'.
'und'+'e'+'cagon'='UNDECAGON'

I've seen this clue in The Independent.
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