I'm developing a rules enforcement system, need help

[Jonix]

Another thing, if a card has a creature sacrifice as an additional casting cost, will the "sacrifice" ability of the sacrificed card trigger?

Example: player casts Bone Splinters. As an additional cost player sacrifices Aerie Ouphes. Will the ability of the Aerie Ouphes trigger?

Yes, but not the ability you mean.

The sacrifice ability of Aerie Ouphes is an activated ability, and this very fact means it NEVER triggers (only triggered abilities do that). If you want to use it, you have to announce it, and sacrifice Aerie Ouphes as its cost.

Aerie Ouphes's persist, on the other hand, is a triggered ability, and that WILL trigger when you sacrifice it (provided other conditions are met).

There is Savra, Queen of the Golgari and Thraximundar, which DO have abilities that specifically trigger on sacrificing something.

I think I haven't made myself clear.

What I meant is, whether or not could a player activate sacrificial ability of the Ouphes and then use the fact of sacrifice in order to cast Bone Splinters? I have a strong feeling that it is impossible, but I want to make sure.

[Jonix]

Answering my own question:

In that case 1 sacrifice would become a cost for 2 different spells/abilities which is impossible.

Silly me