Help with snake's C4 game

[alphabattack]

I noticed that at Apex, Rolex did some cool combos with C4, and the one that is confusing me is the C4 into uair. How did he pull this off. When I try, I can't read which way they'll go when it explodes. Thanks!

 

[EastCoastEddie]

That one happened to be great in it's situation but I wouldn't say it's reliable. He merely caught his opponent off guard and capitalized, which is part of high level play for sure.

Basically you've realized yourself why it's not reliable. Because not only can your opponent DI away from you (left or right) but they can also shield on reaction.