Top 5 Ki attacks that have the biggest amp?

[xmysticgohanx]

?

 

[Evil Vegeta]

I'm sure I'm way off, but here goes. No particular order:

1) A fully charged Kamehameha
2) Makankosappou
3) Light Grenade
4) Hells Flash. Sike. That shit sucks. Final Flash
5) Vanishing Ball

 

[Let's Go Fearless!]

Does Spirit Bomb counts?

 

[xmysticgohanx]

I suppose so

 

[Southern Gothic]

Revenge Death Ball and 10xKamehameha deserve mention.

 

[Papasmurf]

Shin Kikoho

 

[GokhanDBZfan]

That's hard to say.
Amplification depends on how much of their energy the Z-Fighters can concentrate into one point, it actually isn't multiplying their base strength.

 

[kriss-]

Probably the Special Beam Cannon, to lazy to spell it properly.