*First, you need to name your build, so players can easily find it.
Epic's Vortex Crit
*Then, tell us the hero and skills.
Storm Panda
Death Strike
Mana Vortex
Acid Rain
Bonus Life
Elemental Mastery
*Tell us how we should generally level this skills. Do not type out 1 skill per line for all 40 levels of the game; I will deny you based on that alone.
Some research into what your opponent has before hand is a must. Of course main level Acid rain between 4-6, Mastery will become your main farmer later, mastery + ranged agi with Storms good BAT is money, so acid rain is really just for early game farming. Now between Death Strike and Vortex, Death Strike most times takes priority over vortex, toss one point into vortex earlyish for purposes of dispel/anti-summon. If they are not running a mana intensive build main level death strike, only toss points into vortex throughout the game if you need it. But also, don't completely off level it, bounce between Death strike and Vortex still... if that makes sense. You want to have deathstrike half decently leveled by midish game when you start getting big amounts of agility. More or less, unless they are going mana shield / terraptus, I usually go with a 2:1 or 3:1 ratio with deathstrike:mana vortex.
*What makes this build work? How do the skills interact with each other? If this part is really short, your build fails.
This build works off the premise of taking away your opponents mana, while using passive skills to destroy them shortly after. After you vortex them, the huge crits from death strike and spell damage from mastery takes them down real fast. Storm I find works well with this because he has a little bit of range along with one of the faster agility BAT's. The range combined with the shadowstrike from mastery helps with your anti kite, also it will help greatly with creeping. Agility hero's are infamously weak, but storm has enough range to kite the creeps and slaughter with acid rains and mastery. Storm's insta cast also synergizes with acid rain very well. The long and short, you destroy their mana pool with vortex while raping them with massive crits and mastery's amazing spell damage. Vortex combined with mastery also destroys totem and summon builds fairly easily.
*What are your strengths and weaknesses? how will you overcome your biggest weakness?
The biggest strength with the build is it's versatility. Plain and simple it's a jack of all trades, if you don't need to burn their mana you can focus your points into deathstrike and acid rain, and toss a few into vortex. If they are running a hugely mana consuming build, or summons, you can completely destroy their build with vortex, without worrying about your own mana pool, as your main source of damage is coming from auto attack and passive skills. However, the being a jack of all trades, it has no specific strength and can be countered by specific build types. As your main source of damage comes from attack speed and attack damage, soulburn will hurt you. Cripple and the rest however can be dispelled with vortex. Cripple / slow or any other debuffs in combination with soulburn is pretty much insta death. Soulburn will prevent you from casting vortex, and when your slowed and damaged reduce, your mastery is significantly reduced because slower attack = less procs. Damage reducs are a counter too, as your massive crits from deathstrike will now count for nothing. Also, early game gank builds can hurt as well with agility's low health leaves you susceptible to early and mid game ganking. On the contrary, if their running a mana build / summons, it allows to be play completely aggressively with vortex because you don't need to depend on mana at all to farm after level 10ish. Your attack speed witj vortex will allow you to keep up while you make them run back and forth.
*How should this build be played?
Toss vortex's on them when you can to slow them down, it can be a bit tough to gank as you auto attack everything and the shadowstrike is a % chance. But try to toss ganks here and there. The power curve begins around level 14-16 and lasts throughout the game. The death strike crit will hurt them bad all game, the only time the power curve will drastically decline in late game is vs a good strength build as you may not be able to out survive them.
*What general item build should be used on this?
I generally always start off with th agility set, go for the +5 intel and +5 agility, make the imbued cloak, then tiara, the one ring, cloak of fox, and start amassing agility. Like my Timmy build, your farming ability after 10 will mostly be from mastery. The faster your attack speed, the more mastery procs and thus the faster you play. General stagger build most of the agility mid and end game items. However, I find with this build that getting Ring of the Speed demon is bad. The higher crit proc rates take over your death strike proc. Even though you get more crits, the 5X crit from deathstrike will still out damage it. Grab a corruption sword (4x crit for 10%) and more or less you have a 20% chance to crit for 4-5X regular damage. The evasion can be gained from shroud, which will be a must. Focus on agility and damage to maximize your crits and armour, if you need hp go into the tome room and mass up on Hp tomes.