Questions & Answers about Með smá heppni kemur lestin á réttum tíma í dag.
Because Icelandic main clauses usually follow the V2 rule: the finite verb comes in the second position.
Here, Með smá heppni is placed first, so kemur has to come next:
- Með smá heppni = first element
- kemur = second-position verb
- lestin = subject
If you started with the subject instead, you would get Lestin kemur ...
Með normally takes the dative case, so heppni is grammatically dative here.
A useful thing to know is that the form heppni looks the same in more than one case, so the case is not obvious just from the ending. But after með, learners should expect dative.
Smá means a little, a bit of, or small in a very common everyday way.
In this sentence, smá heppni means a bit of luck. Native-English-speaking learners often expect a fully inflected adjective here, but smá is very often used as an indeclinable modifier in modern Icelandic, so it stays smá instead of changing form.