When possible, try to hit what you're trying to kill with the outermost part of the ring.
Also when you get jumped, try to throw this out before their stuff lands on you.
Good for pulling a second camp when you're farming jungle.
Ideally you put this on an auto-attacking core during the fight, but don't hesitate to use it on anyone, just to get the damage going.
Situationally put more points into this early if your lane match-up can support it. Against ranged pokers, you probably can't get too much value out of it, but against, say, Primal Beast, you can drain a ton of damage in the lane. Good for your last hitting/denying, and stops them from last hitting at the same time.
The effect is good, but unreliable in the early game. A value point early is good, but if you find that this messes up your last hitting too much, then skip it until later.
Note that this no longer grants movement speed, so there's very little reason to ever take this early.
When a fight happens, hit this button.
Don't hesitate to use this a couple times in the early game to help farm camps/ancient stacks if you have them. It does help, and the cooldown is low enough that you can get away with it if you aren't getting pushed too hard.
If mid, take an obs
EArly game
Great stats, Razor is an Agility core.
Cheap Mana Regen in the early game. Razor can have mana problems, and this helps a lot for its cost.
Ranged cores get these.
I know you want to keep them in Agility mode for damage (and 0.5% spell amp!), but switching to Strength gives a bit more durability in fights.
These are good. Don't let enemey pop the effect of these.
Get 'em early, mid, and late. When you're farming jungle, or traveling between lanes for a gank, or mustering your team for rosh, or after a team fight.
Maybe a bracer, dust if they have invis/glimmer
Decent regen if you're getting poked too much in the early game. This won't replace Tangoes, but it might help in addition to more Tangoes.
I know you don't *want* to buy dust, but neither does anyone else.
You'll win games by buying dust when other people don't when they have invis heroes/glimmer/shadow blade enjoyers.
Core items
Radiance!
More damage, and survivability... if you can pull it off early.
The attack damage gives you spell amp, which increases the spell damage from the aura. You drain more damage with W, which turns up Radiance even hotter.
Good stats for Razor, and crucially provides the Mirror Image that you might desperately need against roots/silences/enemy Gleipnirs.
If you decide you need this, which you often will, try to save the Mirror Image for those crucial abilites to be cast on you.
Nothing feels quite as bad as running at the enemy, using Mirror Image for the sick DPS, and then getting rooted as you watch them run away :(
It's BKB and you are a carry. You're probably gonna need this.
If you're looking for damage
Big damage (and 4.4% spell amp!) if you don't need other big items.
Big against Medusa, or heroes that might have mana problems.
Pairs nicely with Manta.
The range and stats are nice, but this is mostly another save item, like Manta or BKB.
If you're needing some survivability
Sometimes you need a Pipe, and people won't get it.
Make you even tougher for auto-attacking cores to deal with. You're gonna be in the middle of their team at some point, which is a good time for Shiva's to be active.
