Cursed Rainbow

Deathtouch, Trample, Haste
other Rainbows you control get +1/+1
{t}{x}{x} amass Rainbows x
{t}{1}{b} destroy target non-Rainbow creature
{t}{r}{b}{g} create a 4/3 Rainbow blob with deathtouch, haste and when this creature dies,
if it's power was more than 3 create a copy of
it that is a 1/1