You'll want to increase your Dragon count to ensure that happens with each foe, and note that this is just once per attack no matter how many attack
Tree of Perdition + Tree of Redemption Tree of Perdition and Tree of Redemption focus on exchanging a players life total with these creatures toughness
The otter can replace the second copy of Expansion, giving us some redundancy if we need to use some Expansions on earlier turns (often to turn a counterspell or Duress back at the caster)
Polukranos Reborn/Polukranos, Engine of Ruin Hydras never die Polukranos Reborn is a three-mana Green 4/5 with reach, so it can block flying creatures
In addition to this army of massive creatures, the deck features a number of utility spells including mana rocks, numerous removal spells, ramp spells, counter effects, etc
These are all very fun Dragons to run in your decks, and Im not sure that any of them are anything short of super fun