Lifesteal isn’t a very powerful keywords, especially when it’s on a 1-drop and a minion that will likely die immediately. Early in the game, you don’t really care about your health – you’re either at full (so Lifesteal is completely useless) or nearly full, which makes it a meh early drop. Later in the game, where you might start caring about the health, it’s a 1 mana 2/1, so also pretty useless. This realistically won’t heal you more than once, and often won’t heal you at all. Seems like it’s on a similar power level to Voodoo Doctor – the upside is that you can buff it to heal for more, but the downside is that it’s not guaranteed.
That said, it’s another cheap Lifesteal Beast for Deathstalker Rexxar‘s pool of Beasts. That’s great news. Previously when you wanted Lifesteal, you hoped to get Bloodworm, which was very overpriced. This seems fair if you need some healing in Hunter after you’ve turned into DK.