The most common and most likely answer to this crossword clue is the 13 letter word ETRSTYRAXENNE
E
T
R
S
T
Y
R
A
X
E
N
N
E
Buddy explains!
The straight part
We know that "Tenser, quaking, about war god with cleaver, new" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case tenser, quaking, about war god with cleaver, new = etrstyraxenne.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.