In Dota 2, Riki is my favorite and most played hero. In the 7.23 patch he got several changes to his skillset and stats, an overall nerf and many community members said the hero was dead.
The following are all the changes the hero received in patches 7.23-7.23e
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Patch 7.23
- Agility reduced from 30 + 2.5 to 18 + 1.4 (base damage unaffected)
- Strength gain increased from 1.9 to 2.4
- Base damage increased by 8 overall
- Base health regen increased from 1 to 2
- Base armor increased by 2
- Base movement speed increased from 290 to 315
- Smoke Screen no longer slows (previously was 8/12/16/20%)
- Smoke Screen no longer reduces vision
- Smoke Screen miss rescaled from 10/30/50/70% to 25/35/45/55%
- Smoke Screen radius rescaled from 325 to 280/310/340/370
- Smoke Screen cooldown increased from 17/15/13/11 to 20/17/14/11
- Blink Strike now has 2 charges (with 25/20/15/10 replenish rate)
- Blink Strike damage reduced from 75/90/105/120 to 25/50/75/100
- Cloak and Dagger is now the Ultimate. Has 4/3/2 fade delay. No longer has health regen bonus. Backstab damage is 1/1.5/2x.
- Tricks of the Trade is now a basic ability. Attacks 4 times over 2 seconds, dealing 55/70/85/100% of your damage. Hits random units, including creeps. Cast Range: 400. Radius: 450. Cooldown: 21/18/15/12. Mana cost: 50
- Tricks of the Trade Scepter has been updated. 1000 Cast range, +1 second duration, +2 attacks, targets allied units.
- Level 10 Talent changed from +8 Agility to +25 Attack Speed
- Level 10 Talent increased from +6 Health Regen +8
- Level 15 Talent reduced from -8s Smoke Screen cooldown to -5s
- Level 15 Talent changed from +20% Critical Strike (1.5x) to +35 Damage
- Level 20 Talent increased from +0.3 Backstab Multiplier to +0.5
- Level 25 Talent changed from +300 Tricks of the Trade AoE to -7s Tricks of the Trade Cooldown
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Patch 7.23b
- Cloak and Dagger backstab damage increased from 1/1.5/2 to 1.4/1.8/2.2
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Patch 7.23c
- Base movement speed increased from 315 to 320
- Base HP regen increased from 2 to 3
- Tricks of the Trade damage increased from 55/70/85/100 to 70/80/90/100
- Backstab talent damage increased from 0.5 to 0.8.
First we can see that his base agility and per level increased got a heavy nerf, this is to counteract the fact that his backstab passive, now an ultimate, got a big buff. At level 20 with the backstab talent you deal a whopping 3.0 agility extra backstab damage, it's huge, very huge. What we can take from those changes? Simply, you lost your free base agility, but got a bigger reward for having it, so stack agility items and win. It's that simple.
Next we see that Riki lost his backstab during laning as it is now an ultimate, in compensation he got several buffs to his base stats: He got a massive increase in movement speed, making him one of the fastest heroes in the game, also got his base regen increased. I'd say he is a better laner after those changes, even without his invisibility and backstab.
Regarding his skills
Smoke screen got some nerfs, it won't slow anymore, this, combined with the base agility nerfs, makes diffusal blade even more mandatory on the hero.
Blink strike is a neutral change. Overall the cooldown is bigger, but you get two charges that can enable several plays that weren't possible before.
Tricks of the Trade changes are a buff in my view. Its duration got nerfed, but the cooldown got greatly reduced, meaning you can use it to dodge stuff more freely. The level 25 talent improving this, making the skill super spammable, meaning you get free damage in fights without exposing yourself to any risk. This also makes you way harder to kill, specially in the late game.
For laning and game strategy
You get a huge powerspike at level 6, when you get your backstab and invisibility back. Another powerspike is after buying diffusal blade, which always as the goto first item on Riki, but now it is even more needed.
This means you should be getting those two powerspikes ASAP to have a big impact early on in the game.
Riki's damage scales way harder now, and, combined with the base agility nerfs, he needs agility items as fast as possible.
He also needs levels, his level 20 and 25 talents are HUGE. At level 20 he gets an extra 0.8 backstab damage, at level 25 his Tricks of the Trade cooldown is reduced by 7 seconds, making the skill super spammable.
Because of the above points, I can only see two positions which you can better play Riki in this patch: Safelane core or Midlane. Don't bother with any other position: You need levels and you need lots of gold, there is no other way. And yes, this Riki can easily play into the Midlane assuming you don't run into a hard counter: You have huge regen and damage, just focus on csing and getting level 6 ASAP, then gank other lanes or kill the opposing laner.
For items
As I said before you will need agility items, there is no other way to build the hero. This means no more basher and other stuff you used to buy in earlier patches.
You get Threads (Agility) -> Diffusal blade -> Sange/Yasha or Manta -> Butterfly.
After that, if the game goes that long and you don't have any worthy jungle items, you can get a Daedalus as it will increase your damage tremendously, you will be getting 2k crits often, easily 2-3 hitting most heroes.
You don't care about defense items, at level 25 you will be dealing damage while invulnerable if necessary.
Aghanim is garbage, dont build it. You get one extra second on tricks, get a proper agility item instead.