This is too cheap for the toughness. 4 is a solid blocker for turn 2. Combined with deathtouch, that's too good of a wall. For reference, Giant Scorpion has a toughness of 3 and costs 3 mana. Typically defender would be a drawback, but with that toughness and ability, it's rare that a player would want to attack with this creature anyway. For two mana, a deathtouch is generally looking at 2 toughness. There seems to be a void of 3 and 4 toughness deathtouch (in black at least), and then there are 5 toughness (and usually 5 power) creatures with corresponding mana values of 5 or 6.