Silent Kills

This guide shows the worst item choices for Riki: the active ability from Phase Boots makes you visibile for 3-1.5 seconds (enough for the enemies to see you), Radiance just shows your presence (unless you turn it off, but it would make the Monkey King Bar a much better choice), Mask of Madness removes all the survivability you have (which is already terribly low), the Urn of Shadows after ~8500 gold worth of items is useless and Shiva's Guard is just the luxury item you never want to buy on this Hero.
Rename it "How not to play Riki" and you have a good guide which can make new players understand more of this Hero.

trash items. also shiva's guard? I don't understand how people who clearly don't even understand the basics come on here and think they should make their own guide.

This isn't true.

Anyways, -1 for laughably bad item choices and a worthlessly scattered skill build. Just go cookie cutter Poor Man's Shield, Power Treads, Diffusal Blade, Vladmir's Offering, ( Black King Bar), Butterfly instead of this junk and you'll see much better results.

You said yourself that "Riki's trademark is invisibility", so why do you have so many items which make him visible?

The extra damage / the extra 20% speed phase boots give isn't worth becoming visible. If you really want that extra speed you can buy a pair of Tranquil Boots. +80 Move Speed, health regen and the active ability is a heal. This saves you wasting gold on an urn of shadows.

As for the Radiance... Easily the single worst item you could possibly buy for Riki. Any enemy with a half a brain would just pop a Smoke of Appearance the second they spot the Radiance's effect, and follow it up with a stun.

Mask of Madness is another bad choice for Riki. I can understand why you'd want it for the +100 attack speed / +20% move speed, but a) it makes you visible for the duration of the buff, and b) considering how squishy riki is, taking extra 30% damage could mean the difference between living and dying if you get spotted while trying to gank.

Vladamir's Offering makes much more sense, since you can at least be helping in team fights, even when you're hiding, by giving your team mates your life steal aura, as well as regenerating vital mana so you can spam your blink to catch people trying to run.

You can get as much damage output from your backstab just by buying an eaglesong or a level 3 diffusal blade as you can from a crit with daedalus. You can't crit on backstab either. I don't see any situations where I'd be hitting anyone for a prolonged period of time so I don't really see the daedalus being of much use.

Shiva's Gaurd... Riki is an agility carry, not an intelligence hero. The AOE slow is pretty much useless when you can just get an orb of venom to do the same thing.