Glowmaw, the Shadowreaver

Horror spells you cast have discover X, where X
is that spells mana value.
{1}{u}: Horror creatures you control gain flying
until end of turn.
{2}{g}: Horror creatures you control gain trample
until end of turn.
{4}{b}{b}: If a Horror creature you control would
be destroyed this turn, return it to the battlefield
tapped under its owners control.