TL:DR Version ? http://www.heroesfire.com/hots/talent-calculator?hero=13#hX_f
So lets start with Tier 1:
- Psi-Op Rangefinder
Increases the range of Snipe by 20%.
Best choice in this Tier, additional range is always nice.
- Path of the Wizard
Your Hero gains an extra 5 Mana and 0.2 Mana Regen for every level gained.
Nova has some mana problems mid-late game, but you can do without additional mana or regen just fine. besides, on lvl 15 its just 75 more mana and 7.5 regen. Not really worth it.
- Ambush Snipe
Snipes cast while cloaked deal 20% more damage.
You cant combo this with Overdrive or Wounding shot, so its kinda a waste of a talent. While 20% damage bonus seems nice, inability to combo it with other talents makes it useless.
- Tazer Rounds?
Increases the duration of Pinning Shot?s slow to 3 seconds.
It only adds 0.75 seconds of slow. Same problem as range increase on snipe, it will be useful only in very few cases during the game.
Conclusion of tier 1:
Take range increase, the only choice in this tier really.
- FN92 Sniper Rifle
Nova gains +1 Attack and Vision range.
Bonus is barely noticable and hardly useful. Skip it.
- Vampiric Assault
Basic Attacks heal you for 15% of the damage done.
Even on level 25 your attacks do only ~270 damage. Heal is literally unnoticable for Nova, besides you should be ganking the map, not autoattacking creeps to death.
- Focused Attack
Every 5 seconds, your next Basic Attack deals 50% additional damage.
Bad talent for any hero, but in Nova case its even worse because of low basic attack damage.
- Poison Enemy
Poisons an enemy hero, dealing 180 damage over 6 seconds.
Really good skill for any assassin. Damage scales into lategame quite well and it adds another nuke to your burst arsenal. Clear winner in this tier.
Conclusion of tier 2:
Poison enemy. Its just way too good.
- Battle Momentum
Basic Attacks reduce your Ability cooldowns by 0.5 seconds.
Best choice in this tier, goes really well with rewind. Your damage output is 80% ability damage, so shorter CD really helps.
- Digital Shrapnel
Your Holo Decoy now explodes when it expires or is killed, dealing 50 damage in a small area.
This is just bad. Damage and AOE is so low its laughable. Bad skill.
- Explosive Round?
Snipe also deals 50% damage in a 2 radius around the primary target.
Nice on paper, quite useless in actual game. AOE damage is barely noticable on heroes, so its quite meh.
Conclusion of tier 3:
Battle momentum. Shorter CD on snipe = more kills.
- Triple Tap?
Cooldown: 100 seconds
Reveals target and after 1 second, fires 3 shots dealing 80 damage each.
- Precision Strike
Cooldown: 60 seconds
After a 3 second delay, deals 300 damage in a 4 radius. Unlimited range.
Those highly depend on a map and on your team. Any choice is viable, and under different circumstances you should pick different ult.
Overdrive + Triple Tap = Dead nova from full hp, almost dead Illidan and so on. It does ~3k damage later in the game. Insanely powerful combo. I?d say triple tap is preferred ultimate out of the 2.
However on a map like Cursed Hollow, where there are constant teamfights over tributes, Precision strike may give you way higher damage output.
You should pick ultimate ability based on how game plays out, but triple tap+overdrive is way too deadly to pass up.
- Advanced Cloaking?
While Cloaked, move 25% faster and regenerate an additional 1.17% Health every 2 seconds.
First of all, movespeed buff doesnt apply to you when you are mounted. Unmounted it gives you ~50% bonus of a mount. Overall its a nice talent and it has it use but you just cant skip overdrive so ignore this talent.
- Spell Shield
Periodically reduces the damage received from Hero Abilities by 50%. Stores up to 2 charges.
Nova health is really low, she doesnt have any escape skills so it can save your life in any fight. Really nice skill, but again, overdrive wins.
- Holo Drone
The Decoy gains AI, deals damage with attacks, and uses Snipe and Pinning shot (at reduced damage). You can also control your Decoy while it is active.
Damage is abyssmal. This skill is literally useless. Yes you can control the decoy but damage output is so low its not even funny. Dont pick this skill.
Activate to raise Ability Power by 25% and Mana costs by 40% for 5 seconds.
Turns you into a monster. overdrive + Triple Tap kills any squishy hero right away. Overdrive-snipe-poison-rewind-snipe deals A LOT of damage. God tier talent.
Conclusion for tier 5:
Overdrive is obvious winner, its not even close. Its damage potential is ridiculous.
- Wounding Shot
The target also takes 30% increased damage for 2 seconds.
This is a tricky one.
1)It helps your entire team, but if there is no team around its pretty worthless.
2)If you take ambush talent from the first tier, you cant utilize both damage boosts you have. You either use 20% bonus for sniping out of cloak, or you apply 30% bonus first and then snipe for normal damage.
Personally i think this skill isnt really worth it, as 2 seconds is a really small window to utilize the debuff.
- Blood for Blood
Activate to steal 15% of target enemy?s max Health and slow its Movement Speed by 30% for 3 seconds.
Adds a second slow to your arsenal and does ~600damage on average 4k hp enemy. Not a bad choice either, but i think it loses competition to the last talent in this tree.
Activate to reduce the cooldown of your Basic Abilities by 10 seconds.
This talent makes Nova murdering machine. Your snipe cooldown is 12 seconds, and Slow is 15 seconds. With Rewind you can snipe-slow-rewind-snipe-slow really quick. That is a lot of damage in a very short period of time. You can easily burst down any hero to near death, and then finish them off with precision strike or triple tap. Works especially well with Triple tap upgrade. Add overdrive, and you turn into a damage monster.
Conclusion for tier 6:
Rewind is the best, howerver Blood for blood and wounding shot arent that bad choices either.
Just take your ultimate upgrade. Other skills not really worth it for Nova.
- Fury of the Storm
Basic Attacks bounce twice to nearby enemies for 50% damage.
Nova does not have enough base damage for this talent to be any good.
- Bolt of the Storm
Activate to teleport to the target location.
While useful, its no match to ultimate ability upgrades.
- Fast Reload
If the target of the ability dies shortly after being hit, the cooldown is reset.
Insanely good, whats more to say.
- Precision Barrage?
Precision Strike now holds two charges with a 3 second cooldown between charge use.
2 nukes instead of 1? yes please.
Personally i prefer this build as the most universal: http://www.heroesfire.com/hots/talent-calculator?hero=13#hX_f
I hope this guide has been helpful for you, if you have any questions or suggestions leave comments below.