Answer:
What has been around for millions of years but is never more than a month old?
Is always in front of you but cannot be seen?
I'm a long curved fruit that grows in clusters and has soft pulpy flesh and yellow skin when ripe.
Soldiers fight it but never changes.
Four kings of whom I am one lord. Often on deck but never on board. Though I have a large heart, I am always seen at war. During which I always wear a suit, but never a suit of armor. Who or what am I?
It is something you will never see again.