The best way to go for this deck is:

1/ Be standard, if you are going for that. Sun Titan is not in standard right now. 2/ Get multiples of the cards you want in the strategy you want.

My suggestion for that is GW auras:

4 Ethereal Armor 4 Nylea's Presence 4 Voyaging Satyr 4 Spire Tracer

etc.

thank you Boza ill keep those tips in mind when i next go to the card store

i'd take out the Rot Wolf and Pistus Strike since you're not playing infect.

44hydra44 i will take out rot wolf, but pistus strike must stay, i play a lot of people with overpowered flying cards, that card is just insurance

then i'd remove the pistus strike and add in Arbor Colossus , Crushing Vines , Deadly Recluse , Eaten by Spiders , Plummet , Stingerfling Spider , Whirlwind , Bow of Nylea , Corrosive Gale , Silklash Spider or finally Windstorm and the list still goes on most people will have at least some of these lying around at home in their uncommon/common stacks at home or you'll be able to pick one up in a booster pack.

And in terms of strengthening creatures, you've got even more choices. Rancor , Giant Growth , Mutagenic Growth , Unflinching Courage Hopeful Eidolon or Feral Invocation just to name a few

thank you 44hydra44

...Yup this is a beginner deck....get more than 1 of everything

Is this for casual Modern play? OR were you looking to be a competitive player.

Yes Spootyone causal modern play

Alright well I'll be honest I've never played modern in my life lol. Similarly, giving someone advice on a casual deck can be sort of tricky because the tendency is to aim that deck in a competitive (i.e. stronger) direction. However, I see what you have here so let me see what I can do.

Garruk, Primal Hunter is hands-down the strongest card in your deck. the only card that comes close is Sun Titan . Perhaps you could add ways to recur Garruk such as Eternal Witness . She even combos oh-so well with Sun Titan and is only a couple bucks. Similarly, there's Regrowth .

Harmonize is a means of green card draw and isn't too expensive. It can allow you to get to your bombs quicker.

Trostani, Selesnya's Voice is a litle more costly, but gives you more lifegain and sustainability while also giving you an outlet to populate your tokens.

Speaking of tokens, Call of the Conclave is fairly cheap and a great card.

I think Gyre Sage could be better utilized in a more ramp-centric deck featuring things like Elvish Mystic , Arbor Elf , Avacyn's Pilgrim , Farseek , Sylvan Caryatid , Birds of Paradise and then some high-costed heavy-hitters.

Nav Squad Commandos are kinda lame. Their battalion rarely seemed to go off for me when I used them.

Common Bond works incredibly well with the new heroic ability introduced in theros. Perhaps you could try out something like Fabled Hero or Phalanx Leader ?

And lastly, Path to Exile and/or Swords to Plowshares or amazing removal spells that you should try to take advantage of.

Thanks a lot Spootyone if it is not too much to ask, next time you test play a deck, could you play against mine? It would be such an honor, thanks again

I would strive for consistency with your power cards. If you want to keep life gain effects, look at what value you're getting for the mana. Centaur Healer and Unflinching Courage are a good start to work with. They're fairly inexpensive so if you don't have a large budget to work with I'd recommend using at least 3 of each.

Fleecemane Lion is also good to work with, and I'd probably suggest 4 early mana producing creatures. Noble Hierarch might be ideal but very expensive, you could use Avacyn's Pilgrim or Elvish Mystic to accomplish the task.

Also, is this specifically for casual play or are you planning to build it into a certain format?

Nice!!! :D Maybe you can check out some of my decks!

your deck SUCKS

im sorry but you have almost no good combos and its not even modern legal. you need to take out sustainer of the realm. also to have a good deck you need more than just 1 of each card. and the point of modern is to use good card that are not stranded legal not bad ones. sorry to diss on you so much and its just my opinion so you dont have to change anything

Hans49163. Wanna know why it sucks? It was the first deck I ever made lol. Look at the post date. Maybe you should look at my other decks