If a creature has multiple instances of bushido, each triggers separately.
July 13, 2013 · Magic 2014
If a permanent has multiple instances of soulshift, each triggers separately.
September 30, 2011 · Innistrad
You can't choose to use a splice ability if you can't make the required choices (targets, etc.) for that card's instructions. You can't splice any one card onto the same spell more than once. If you're splicing more than one card onto a spell, reveal them all at once and choose the order in which their instructions will be followed. The instructions on the main spell have to be followed first.
June 17, 2011 · Commander 2011
You can’t choose to use a splice ability if you can’t make the required choices (targets,
April 1, 2011 · Duel Decks: Knights vs. Dragons
The permanent is sacrificed at the same time the spell is announced (see rule 601.2a). The total cost of the spell is reduced by the sacrificed permanent's mana cost (see rule 601.2e).
February 4, 2011 · Mirrodin Besieged
The permanent is sacrificed at the same time the spell is announced (see rule 601.2a). The total cost of the spell is reduced by the sacrificed permanent’s mana cost (see rule 601.2e).
October 1, 2010 · Scars of Mirrodin
The permanent is sacrificed at the same time the spell is announced (see rule 601.2a). The
February 1, 2010 · Worldwake
The permanent is sacrificed at the same time the spell is announced (see rule 601.2a). The total cost of the spell is reduced by the sacrificed permanent's mana cost (see rule 601.2e).