KILL THEM IN TWO SHOTS

I can understand the concept behind this way-off-meta build for Arena purposes (as he states in his write-up). This person is specifically NOT wanting to go with the traditional ability damage route. In a non-conquest mode for funsies, I can accept that...but given that, this build is far from optimal for its purpose.

I can see a unique, niche situation where a high MS/chase Loki build could work and be fun...but it's typically not a good idea. I would consider trolling with this build if the following was in place:

• Playing with friends who I know can shoulder the main teamfight load, because this build sure as hell won't be able to teamfight (not like the ability one will either). But at least with the ability one, you can ult in, 100-0 a squishy, taking them out of the fight, to give the rest of your team a potential man advantage. This one is unlikely to do that due to not having much non-stack-requiring penetration, and also not often due to not having ANY CDR. Your whole gameplay will be sitting back and waiting for a squishy enemy to get hurt and retreat, or go off on their own way away from the enemy. That very much limits when you can engage properly.
  
  
• I would need to very closely monitor enemy ability use. Loki is very vulnerable to CC and damage, which is why his best strength is getting in, bursting, and getting out. There's not much "bursting" going on in this build, since you're basic attacking, so you'll sometimes be exposed for a longer period of time.
  
  
• I could tell early game that the competition was lower level and their awareness sucked.

One thing I'm guessing you (Loki the Speedster) may not be aware of is the concept of diminishing returns with regard to movement speed. You can learn or refresh yourself with The Word of Thoth, section 1.6. In essence, you're blowing way past the soft MS cap, and getting less added MS than you would otherwise expect. HUUUUGE inefficiencies in your current build.

Basically, you've taken the concept of chasing people down, and overdone it to the extent that it's hurting the potential this build would otherwise have to deal better damage.

I personally feel that, even in a basic attack/MS focused build, you really do still want CDR. The easiest and most obvious solution there is to get Jotunn's Wrath.

In terms of dropping items, if I were to try to make this build more effective, I'd drop Atalanta's Bow, because the passive MS boost requires you to hit the enemy with basics, but you should already be able to stick to the enemy with Hastened Katana. In addition, I'd probably also drop Warrior Tabi, because as stated above, diminishing returns on MS. Keep in mind, you also get a huge 35% MS boost from Vanish.

I'd also contemplate dropping Heartseeker, as it might be a bit difficult to build stacks efficiently...maybe it's okay, but I'd probably consider a bit later in the build due to the passive having better effect once more power is built.

I'd thus replace Atalanta's and Warrior Tabi, and rearrange the build order as such:

• Hastened Katana + Stone Cutting Sword (order as preferred). These 2 items will give you 20% MS, forming your normal MS base. SCS in a basic attack focus will also provide the needed base pen effect to fight those squishies you need to be targeting. You'll also be able to stick to enemies that you do catch retreating or unawares.
  
  
• Jotunn's Wrath, because you seriously still need to use abilities often.
  
  
• Heartseeker OR Masamune
  
  
• Rage + Deathbringer OR Qin's Sais + Asi

This is seriously so outside of meta, it's an absolute troll type build...but that's probably what I would do to shore up the weak parts of this build and provide better potential basic attack DPS.

This is more of a play style. I used just about every build you’ll suggest. I noticed for me it’s hard to get my auto attacks off when I don’t have movement speed. If you don’t have that probable then thats perfect. I don’t realky like starting trans because I’d rather farm kills than minions. I also know that movement speed is one of the best defensives and it’s prevented me from feeding lots of times because of your escapablity. You don’t need a billion power and pen to kill a targets. Heart seeker and stone cutting sword give decent pen to start with. Having this much movement speed just really helps you get in good position while punishing others in bad positions. This obviously works great with his 1 and ult