Lucifer, unwanted heir

Flying
{t}: sacrifice a creature draw two cards
when Lucifer enters the battlefield or attacks,
you may discard up to four cards from your hand,
Lucifer gains abilitys acording to the amount
of cards discarted,cost reduces from each
card discarted by this effect previously,:
1+: gains a haste and a deathtouth counter;
2+: gains double strike counter and ward 1;
3+: gains a +1/+1 counter