Legendary is a supertype that can apply to many card types, including lands, artifacts, enchantments, and planeswalkers
The not so low casting cost and the fact that it costs two white mana make it impossible to play more than one, but adding one of those to the maindeck has resulted in a big increase of flexibility when it comes to dealing with stuff that has entered the battlefield already
What would happen if I kick Comet Storm twice and conspire it with Wort, the Raidmother (and why)
Players generally want to play two cards a turn, so youll be getting a fair amount of draw triggers here
Any creature you enchant not only gets +1/+1 but also becomes unblockable by anything but defender creatures
Blocking creatures commanded by this card is already a losing proposition, and few commanders give you a better incentive to play with -1/-1 counters or toughness-based removal like Last Gasp