Need clarification on the Stack

[lumostation]

Okay, so possibly a total noob question, but I just need some clarification on the Stack. I'm pretty sure I'm.l playing correctly, but this seems so cheaty to me:

Say I'm an attack... After declaring attackers/blockers, it's okay to use an instant to buff up a creatures that's not blocked, right? So, I can buff a creature's attack and basically trick my opponent who decided to not block the creature because they didn't think it was a threat?

Thanks!

 

[Barty64]

Yeah, that is something you can do, it does feel cheap, but is allowed within the rules.

 

[lumostation]

Jeez, this game is ruthless. Thanks for the clarification!