Salazar Slytherin

Deathtouch
For each creature with a Slytherin House Crest (SHC) you control, Salazar Slytherin gains +1/+1. These creatures gain +2/+2 and deathtouch.
If you control 6 or more creatures with a SHC, at the beginning of your upkeep, if you don't already control a Basilisk, create a +15/+10 Basilisk with Trample