Bloodthirsty Strike is a flexible card because it can also be useful to cast it on an opposing creature when needed. For instance, imagine you're in a zone with your [mwcard=MW1C23]Malacoda[/mwcard], who had been on guard but was attacked by one of your opponent's other creatures. It's your mage's turn to act, and your mage is at risk of dying if an opponent's buffed creature in the zone were to attack. One option is to move out of the zone and cast Bloodthirsty Strike on your opponent's creature. This way, it has to attack a damaged living creature in its zone = Malacoda; while Bloodthirsty, a creature can't leave the zone to attack your mage! Another option might have been to cast [mwcard=MWSTX2FFI06]Defend[/mwcard] on Malacoda, but the Bloodthirsty trait even forces an Elusive creature to attack a damaged living creature in the zone. So... in addition to being a buff for your own creature, it can be used kind of like Taunt in a pinch.
Of course, you're giving that creature an extra 2 dice against Malacoda... but it could save your mage's life.