In Japanese verbs can directly modify nouns in a manner similar to relative clauses in English. So they don't necessarily only come at the end of a sentence.
http://en.wikipedia.org/wiki/Relative_clause#Japanese
this construction xxのつくzz
would be something like xx category zz, or xx series zz, or xx class yy
今度は㋮のつく最終兵器!
Now,( Maru Ma ㋮) M class ultimate weapon.
although you might go with demon 魔 instead of M
今度 seems to be part of an ascending series in these titles.
今日から、今度、今夜、明日
and ㋮のつく is also a constant like "Harry Potter and the... "
Titles are often difficult to translate.
so maybe,
"Now! the Ultimate ㋮ Demon Weapon!"
or just "The Ultimate Weapon!"
--edit--
to put in url reference