{T}: Draw a card, then discard a card.
{2}{U}{B}, {T}, Sacrifice Obsessive Stitcher: Return target creature card from your graveyard to the battlefield.
Obsessive Stitcher can't be the target of its last ability.
You draw a card and discard a card all while Obsessive Stitcher's first ability is resolving. Nothing can happen between the two, and no player may choose to take actions.