Hi Smash666,
You have some good cards there.
Here’s my opinion on your deck, maybe others will contribute something as well.
Support
Hixus Prison Warden (This is really a good card. Once you have that out and could reinforce it over the game, you should have no problem beating Tezzeret, who has no support removal.)
Campaign of Vengeance (Can be great, but since you only have three creatures and it takes a long time to have them all out, you will never have a lot of benefit for your invested mana most of the time)
Aether Hub (Not a bad card, but you run mainly cheap cards, so I don’t feel it really needed here)
Gonthi’s Aether Heart (Generally a great card, and you should be able to use it against Tezzeret, since he energizes the board quite well)
Spells
Aerial Modification (In general a good card, but I don’t think that it will give you enough edge against Tezzeret)
Give no Ground (I really like this card and it’s great in PVP. Here I feel like Tezzeret creature grow to powerful to quickly to give you an edge with this)
Ondu Rising (Also a nice card, but one of your creatures already has lifelink and this card doesn’t support you well against 512 hit points. Again, it can give you an edge in a PVP game where hit points are kind of equal)
Creatures
Maulfist Doorbuster (I guess you have it in here to disable the defender and push though with your attack? I’m not sure if this will work on the long run)
Serene Steward (Generally a good card, when you have Lone Rider in the first spot)
Lone Rider (Great card, once you can get it to have a lot of power and toughness)
(In general I would say, that the problem of you deck is, that you have 3 spells that all boost creature, but you only have 3 creatures in your deck, so it is not unlikey, that you have a lot of cards in hand, that you can’t use. Furthermore these spells can’t really deal with Heart of Kiran at an early stage of the game.)
I would say, you have to focus. Since you have Hixus, it is not a bad idea to go for this card. Until you you have that cards out, you have to have control. So, how about some thing like this:
Supports
Hixus, Prison Warden
Deadlock Trap
Suppression bond (may look like to much, but the more disable you have you earlier can establish it, until you have Hixus on the board and if early Hixus is destroyed you may have at least the first creature disabled)
Something for drawing cards (Tamyo’s Journal or Fevered Vision available?)
Creatures
Serene Steward
Lone Rider
Something with lifelink (?) or Skysovereign Consul Flagship or none
Spells
Encircling Fissure
Alchemist’s Vial
Humble the Brute
Swift Reckoning
(If no 3rd creature chosen maybe Magmatic Insight for more card draw)
The strategy is quite simple, get hixus out as fast and as often as you can.
All the rest should be around disable, drawing cards or remove creatures.
Once Hixus is established on the board, you should be able just to watch the show, reinforce Serene or Lone rider whenever possible and watch them grow.
Downside is, that it is going to be a long game for sure.
A second lifelink creature could add some safety on the long run.
Do you have other level 60 PW? Sorin for example? I just a Sorin deck with lifelink creature and removals to some success until I used Dovin Baan with Baral…
If you want more advise: ask your question there (and tag AngelForge there, if you want especially his advice ;))