The Strongest Weapon in The Game

I only found out about the Zodiac Spear 8 hours into playing from gamefaqs, and stupidly I already opened the treasures in 2 of the 4 areas that had to be left alone. I love to make my chracters as strong as possible, the best being the legendary weapons in FFX. That said, I'm sure it is, but just to make sure, it's still possible to beat the game without it, right? Or is it the easiest of the strong weapons to get? I need to put this at ease because you could not imagine the disappointment I felt. Thanks in advance.

You can beat the game without it. But there is anothor way to get it to. And the zodic spears isn't the strongest weapin wyrmhero is.boboboj

Here is how you get it from sephorthy guide.

Location 2 - Henne Mines, East hidden section.
           - Go North from the Gate Crystal, then East.
           - In the secret section, turn right from the second junction. Follow
             the way until you reach to next mine route. Now pay attention
             to right side. Around crates, there is a small area which didn't
             shown in the map. The treasure chest will appear there.
           - Only 10% chance you can find the treasure, and only 10% chance
             could get this weapon.

- Here is the point
http://img.photobucket.com/albums/v515/sephiroth_y/Guide/hen_str_hal.jpg

* Requirement - Must have at least 10 espers and finish Mind Flayer mob hunt
                mission (rank B).
              - Go Land Of The Garif find the geomancer to get some info, he's
                located at opposite of the Item Shop. Now back to Henne Mines,
                the gate to East has been unlocked.
              - Equip Diamond Armlet.

Here is how you get it from sephorthy guide.

Location 2 - Henne Mines, East hidden section.
           - Go North from the Gate Crystal, then East.
           - In the secret section, turn right from the second junction. Follow
             the way until you reach to next mine route. Now pay attention
             to right side. Around crates, there is a small area which didn't
             shown in the map. The treasure chest will appear there.
           - Only 10% chance you can find the treasure, and only 10% chance
             could get this weapon.

- Here is the point
http://img.photobucket.com/albums/v515/sephiroth_y/Guide/hen_str_hal.jpg

* Requirement - Must have at least 10 espers and finish Mind Flayer mob hunt
                mission (rank B).
              - Go Land Of The Garif find the geomancer to get some info, he's
                located at opposite of the Item Shop. Now back to Henne Mines,
                the gate to East has been unlocked.
              - Equip Diamond Armlet.

boboboj