"The Final Countdown" synth is the Sawtooth version of the "Lucky Man" synth lead which was made with Square waves.... both Synth Leads with plenty of portamento.

You could start from scratch or simply start with the Synth Lead "Lucky"
Classic Square wave sound. Navigate to the Element screens and change the two Elements to Sawtooths...

Press [EDIT]
Press [PART SELECT 1]
In the screen touch "ELEM1" or press the first button in row three
Touch "Osc/Tune"
Touch the box at the top that will let you select Waveform: Bank, Number, Category, Name
A pop-in menu appears...
Touch "Search"

I suggest using the PROPHET V Sawtooth waves to build this sound...
On the Search screen in the box with the magnifying glass type "P5"
This will find the seven Prophet V Sawtooth Waveforms ... each is either Sawtooth up or down, with different phase relationships- pick one for Element 1, another for Element 2; use two different ones to create a natural movement in the sound.

You can experiment with adding more sawtooths... by substituting the Waveform for "Lucky" we take a shortcut to setting up the portamento etc... but feel free to tweak to your liking.

That should get you close. Let us know.

Bad Mister...thanks for this..
I agreed with 3 lead sound..works o.k

The final countdown sound for montage??
Is there any idea that the factory sound would be for that song?

Hi Robert Bad Mister did explain a easy way to edit a -Basic- factory sound on the Yamaha Montage, i get the idea that most synthesizer users these days
have forgotten, that the standard factory sounds are just a -BASIC- starting point to can go edit create change mix combine design to work on a wat ever possible sound / instruments / new sound or a wat ever cover instruments sounds. that's the whole intent which a modern synthesizer is designed for.!!
and sure on the Yamaha Montage with his many sound effects settings options you can reproduce almost any cover instruments sounds that comes very very close to the Original Bands & Artists sound atmosphere..That is for me aways the challenge and wat i do most on my Yamaha Motif and Montage synhesizers. to create the many -70's-80's-90's-2000's- cover instruments sounds user banks for my many multi track recording instrumental / backing tracks cover songs creations. it is a matter of course to look a little deeper in your synthesizer to discover and explore that amazing unlimited sound / music production beast like the Yamaha Montage.. BTW it is also the best fast and most easy way to learn your syntyhesizer as best have fun to discover explore your Montage Grts Ron