Kicker
and/or
(You may pay an additional and/or as you cast this spell.)
If Necravolver was kicked with its
kicker, it enters the battlefield with two +1/+1 counters on it and with
trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.).
If Necravolver was kicked with its
kicker, it enters the battlefield with a +1/+1 counter on it and with "Whenever Necravolver deals damage, you gain that much life."