Over the past few years, Ark Invest CEO Cathie Wood has become one of the world's most closely followed investors. Wood is famous for betting big on potentially explosive growth stocks, and her investment firm has seen strong results for its exchange-traded funds (ETFs) this year. 

Her firm's flagship ARK Innovation ETF is up roughly 24% year to date even after recent bouts of market volatility, and she has continued to invest in promising artificial intelligence (AI) stocks. If you're interested in taking a couple pages out of Wood's playbook in hopes of scoring huge returns, consider two AI players with fantastic return potential that she's been buying recently. 

1. Palantir

Even though Palantir's (PLTR 1.56%) share price has risen 120% so far in 2023, the stock is still down 63% from its high in 2021 and could have huge upside potential. Wood certainty seems to think so. Ark Invest purchased over 1 million shares of Palantir stock in September for various funds, and it wouldn't be surprising to see the famous growth investor continue to load up on the early artificial intelligence leader's stock.

In May, Palantir launched Artificial Intelligence Platform (AIP) -- a software suite tailored for both national defense and enterprise business applications. Through AIP, public and private-sector customers can use large language models and AI to help build applications and recommend and automate processes and actions. 

Palantir's AIP accumulated more than 100 customers by the end of its second quarter, which ended June 30. Even better, the data technologies specialist said that it was in conversations with 300 other enterprise customers that were potentially interested in purchasing the service.

After posting 13% year-over-year sales growth in Q2, Palantir guided for revenue growth to accelerate to 16% in the current quarter. With adoption and usage scaling for AIP and other artificial intelligence tools seemingly still in the early stages of unfolding, the business could be poised for powerful sales growth down the line.

Crucially, Palantir has also shifted into posting profits on a GAAP basis, so strong revenue growth can be expected to correspond with increases for earnings per share even as the company invests in new technologies. With sales growth accelerating, profit margins improving, and huge AI opportunities still ahead, Palantir has breakout potential.

2. Roblox 

Roblox (RBLX 1.54%) has also been one of Wood's biggest stock bets in September, as Ark has purchased more than 1 million shares of the company's stock across its ETFs. With the company's share price still down 81% from the peak that it reached in November 2021, now looks like a smart time to build a position in this underappreciated AI player. 

While Roblox understandably has a greater association with the metaverse trend, the business stands to benefit from artificial intelligence in a variety of ways. For starters, the company is gearing up to make a big push into digital advertising. With 65.5 million average daily active users (DAUs) last quarter and 14 billion total engagement hours on the platform, Roblox has a sizable and highly active user base. The company is in the early stages of rolling out its own ads network and will use AI and machine learning to improve advertising targeting -- just as social media leaders including Meta Platforms and Alphabet are doing. 

Roblox already introduced generative AI software to help content creators create visuals and complete code, and it will also be releasing tools that allow regular users on the platform to generate characters, items, and other 3D objects. Within the broader Roblox ecosystem, the possibility also exists for creators to introduce and monetize their own generative AI tools.

Roblox remains in the very early stages of tapping into digital advertising and other AI-powered opportunities. If these initiatives wind up being successful, investors who buy the stock at today's prices and hold for the long term could wind up scoring serious returns.