Okay, to start with, every Survivor T2 deck NEEDS a leader. This is based on preference, so decide whether you prefer Ambre, Morphun, Hugo, Eyrik or Eklore (other leaders aren't really seen much in T2).
Now decide if you want to make a full deck or half deck. Half decks generally tend to work better than full decks.
Some solid possible clans are Ulu Watu, Sakrohm, Junkz, Nightmare...
Really it's based on preference. But I like Morphun paired with Graksmxxt and Uranus, along with 5 other cards from any clan you want. Trial a few decks and decide what's best for you.
Hugo is the best leader once you have less than 10 pills. At that point, you will need to force your opponent to pill every round, even if you don't. This is why he is my favorite hero to use (although Eyrik, Morphun and even Ambre are ok up to 10 pills to start)
I also like Graks and Uranus, but TrinmkT is also nice to use. I was also fortunate to borrow another useful card from Sakrohm to make quite a scary deck. Pair them up with Nightmare (Kolos, Nista, Ghumbo) and you have a nasty deck