Example Sentence: Ich liebe Einhörner (I love unicorns)
Yes, i think it's always like this. I come from Germany and i don't know a -horn word which is not neuter. Because The word EINHORN has two parts: 1. EIN, 2. HORN and the article (der/ die/ das) goes always with the second part of this word, so with HORN and you say " ein schönes Horn " ( a beautiful horn). And the article definite if it's neuter, masculinum or femininum.
If you didn't understood it you can ask me again! ;-) [German is difficult]
Thanks so much for answering this question for me! I agree, German is difficult! I like the way it sounds. It is a very interesting language.