Squealing Devil [Dissension]

Description

Set:	Dissension
Type:	Creature — Devil
Rarity:	Uncommon
Cost:	{1}{R}

Fear (This creature can't be blocked except by artifact creatures and/or black creatures.)
When Squealing Devil enters the battlefield, you may pay {X}. If you do, target creature gets +X/+0 until end of turn.
When Squealing Devil enters the battlefield, sacrifice it unless {B} was spent to cast it.