SoA = Stop Opp Ability
SoB = Stop Opp Bonus
(R), (U), (C) = Rare, Uncommon, Common. You can safely ignore this.
If you play Rescue, you really should play 8 of them since their bonus uses Support. The +1 damage from Timber isn't generally worth the -3 attack, especially since Timber himself has poor stats for a 5*.
Take a look at the Rescue cards and see which ones catch your fancy. Read the reviews to get a general idea of their strengths and weaknesses, but ultimately you should pick a deck to fit your personal style. Aside from acacao's suggestions, lots of other cheap Rescue cards are playable, like Wesley, Joana, Krash, Tanner and Suzie.