is an enchantment allowing you to sacrifice a creature to deal 1 damage to a target creature or player. It is an ability and not a spell. While abilities may be countered, an instant countering a spell will not work here.
is an alternate cost to cast a creature. You may pay the normal cost, as listed in the upper right-hand corner and place the creature on the battlefield as usual.
You also are given the choice to place the card face down as a 2/2 creature for (3) generic mana.
While it’s played face-down, you treat it as a 2/2 creature entitled to enchantments and artifacts. But it has no color, name, or creature type. Therefore, spells or abilities that affect specific or targeted color, name, or creature type is ineffective to face-down cards.
When you choose to pay the Morph cost, and some cards carry none, you flip the card over, reveal your card and activate the triggered ability. It’s an interesting choice of cards if you choose surprise as one of your strategies. Morphing and any action taken happens immediately and cannot be countered.
Recommend the following video, from YouTube.
Allows you place the creature at any time you could cast an instant. Another example using surprise.