quick reminder, no he hasnt the 2nd highest agi gain, already bloodseeker and pa come in my mind that have more. Rikis backstab clearly ISNT op, nothing in the game really is. Riki is a carry meaning, as the definition says, he will get very powerful as he gains a gold advantage over the game. If the enemy team isnt able to handle a permanent invisible guy thats their fault. Dota is already very balanced and with just dust on everybody, maybe sentrys here and there and riki wont be able to do anything the whole game because remember, he has a relatively low strenght gain for beeing meele

Sange and Yasha almost all rikis get ti with Basher makes riki tanky enough