This deck's strategy revolves around the multiplication of +1/+1 counters on creatures to win the game.
Hardened Scales is dirt cheap to cast and can add tons of +1/+1 counters on your creatures over the course of the game.
Servant of the Scale is a perfect one drop for this deck and can potentially be a big buff for another creature if it dies. It can become an excellent blocker if your opponent does not want to kill it and move the +1/+1 counters to a stronger creature. It works really well with Hardened Scales.
Anafenza, Kin-Tree Spirit is a creature and a cheap way to trigger bolster multiple times during a game.
Den Protector is excellent and can fetch back anything in the graveyard (Inspiring Call is a pretty nice target though!). With some +1/+1 counters or Gleam of Authority, it can be pretty hard to block him as well. The fact that he is megamorph rather than morph makes this card completely ridiculous in this deck.
Hidden Dragonslayer is a good creature and a good removal combined in one card. The lifelink is pretty good if it comes down to a race. The fact that he is megamorph rather than morph is even better in this deck.
Managorger Hydra can grow extremely quickly with Hardened Scales. It needs to be dealt with ASAP by your opponent. It will turn any other creature enchanted with Gleam of Authority into an absolute monster.
Undergrowth Champion grows more slowly, but it sticks better to the board.
Daghatar the Adamant can be used to steal +1/+1 counters from your opponent's creatures. He can also move them around during combat to mess up your opponent's plans. He can actually start to generate more +1/+1 counters with Hardened Scales. He provides a nice buff to other creatures enchanted with Gleam of Authority.
Elite Scaleguard is the finisher. Once you have a board big enough to kill your opponent, simply play him, attack with everything and tap all the blockers. Unless your opponent has instant removal for a 2/3 (or 4/5?) the game should be over.
Gleam of Authority is simply overpowered in this deck if you get it to stick to a creature. Be careful when you play this card. It has the potential to win you the game or to allow your opponent to trade you 2:1. Den Protector and Hidden Dragonslayer are really nice target for this aura. It is another cheap way to bolster during the game.
Lastly, we play Inspiring Call to counter removal and mass removal. In this deck, it is also a great spell for card draw since it is relatively easy to have +1/+1 on all your creatures.