For example, if your Phantasmal Image is a copy of Geralf’s Messenger and it dies (without any counters on it), it will be returned to the battlefield with a +1/+1 counter, and you may choose something to copy. If the original Geralf’s Messenger is no longer in play, you can’t have the image enter as a copy of that, even though it was one when it died. If you can’t or choose not to copy something else, the Image will just enter as a 1/1 creature (because of the +1/+1 counter), and it won’t have the “Sacrifice me when I’m targeted” ability (that ability is only added as part of the copy effect). So if you ever see a Phantasmal Image on the battlefield with a sword equipped to it, that’s probably how it happened.
Today’s Rules Tip suggestion submitted via the “Suggest a Rules Tip” form by Ryan Porter