Text (10): Enchant creature. ; All creatures able to block enchanted creature do so.
Lure does not give a creature the ability to block the Lured creature, it just forces those creatures which are already able to block the Lured creature to do so. [D'Angelo 1994/06/01]
Opponent does not have to power special effects in an attempt to make all creatures block the Lured creature. For example, you do not need to power a Goblin Balloon Brigade to block a flying creature with Lure, but if you do power it, the Brigade must block. [bethmo 1994/08/01] More specifically, even a cost of zero mana is an optional cost you can choose not to pay. [WotC Rules Team 2000/02/16]
If a Lured creature is in a band, only blockers able to block the Lured creature are affected by the Lure. [bethmo 1994/10/01]