Its a neat card, but its just not good by itself
Although Lifestream's Blessing's full potential only activates by paying its Foretell costs, keeping the card handy for the moment you set down a massive creature is a great way to avoid its cancellation while acting as an insurance policy for your life total
The only giveaway left is that it has a significantly glossier back than a real card, even more so than a real card with Japanese printing (they are known to be glossier than US-printed cards)
And as you venture into the magical realms of MTG, don't forget to safeguard your valuable card collection
When you're sad to use a card to make a fair trade that's often the sign you are on to something, and it would be interesting to see how popular a three-mana version would be if it could hit players
Many of the best sacrifice outlets are just ways to exchange tokens for mana or cards, and you need to get considerable fodder in play to even set those up