Rulings

• 2005-04-01
  When Reweave resolves it uses the type(s) that the permanent had right before it was sacrificed.
• 2005-11-01
  The player reveals cards only if the targeted permanent gets sacrificed.
• 2008-04-01
  With the introduction of the Tribal type it became possible for an instant or sorcery card to share a type with the sacrificed permanent (ie, a Tribal instant card shares a type with a Tribal Enchantment card). Reweave has received errata so that the effect looks for a *permanent* card that shares a type with the sacrificed permanent. A permanent card is a card that could be put onto the battlefield, which is any card that isn't an instant or sorcery.
• 2013-06-07
  You reveal all cards you intend to splice at the same time. Each individual card can be spliced only once onto any one spell.
• 2013-06-07
  A card with a splice ability can't be spliced onto itself because the spell is on the stack (and not in your hand) when you reveal the cards you want to splice onto it.
• 2013-06-07
  You choose all targets for the spell after revealing cards you want to splice, including any targets required by the text of any of those cards. You may choose a different target for each instance of the word "target" on the resulting spell.
• 2013-06-07
  If all of the spell's targets are illegal when the spell tries to resolve, it will be countered and none of its effects will happen.