Want to earn potentially massive returns? Look no further than crypto. While the market is in a slump right now, it has a track record of bouncing back from its declines as the technology and its use-cases improve.

Let's explore why Cardano (ADA 9.46%) and The Sandbox (SAND 1.73%) could help power the crypto rebound and boost your portfolio. 

1. Cardano

Launched in 2017, Cardano is a blockchain network designed to host decentralized applications (dApps) -- autonomous programs that use self-executing smart contracts to provide services. Cardano boasts impressive technical specs, and its active development team could help it maintain a long-term edge over rivals. 

Green stock chart moving upwards

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According to data from coinmarketcap.com, Cardano can process as much as 257 transactions per second, compared to Bitcoin's 4.6 and Ethereum's 15-20. This speed can be credited to its consensus mechanism Ouroboros -- a proof-of-stake system (PoS) where miners verify transactions using existing coins instead of solving complex puzzles like older proof-of-work (PoW) blockchains. 

That said, Cardano is still significantly slower than other PoS blockchains like Solana, which can process 50,000 transactions per second. But Cardano's developer, Input Output Hong Kong (IOHK), isn't resting on its laurels. 

The developers plan to boost scalability through an update called Hydra which could go live by late 2022. Hydra is designed to increase Cardano's processing efficiency and could take its transaction capacity to one million per second -- although IOHK stresses that this is an aspirational target, and the main goal is to scale the platform with demand.  

2. Terra

Founded in 2018, Terra is a blockchain platform designed to enable the use of stablecoins, which are cryptocurrencies that track traditional currencies like the U.S. dollar or Euro. The asset looks poised for success because of its potential for real-world utility. 

While cryptocurrencies are already widely-used to store value and make payments, their volatility can be a big challenge. For example, many merchants would be hesitant to accept crypto as payment because they don't know what it will be worth when they convert it to dollars. Likewise, many savers don't want to see their net worth rapidly fluctuate compared to everyday expenses. Terra aims to solve these problems by creating a portfolio of stable digital assets. 

The Terra protocol consists of two types of tokens: Terra, and LUNA. Terra refers to a suite of stable coins that track the price of real-world currencies such as the dollar (TerraUSD) or the Koren Won (TerraKRW). LUNA is the blockchain's native token, which absorbs the volatility of the Terra stablecoins and grows based on user uptake of the platform. 

With a market cap of $27 billion, Terra's native token, LUNA is already the 8th largest cryptocurrency, indicating healthy demand for the service it provides. The platform is poised for continued growth as people become more comfortable saving and spending digital assets. 

Betting on a crypto rebound 

Cryptocurrency has been in a slump recently, with the total market value down 23% to $1.7 trillion year to date. But the industry has a track record of bouncing back from its declines. Cardano and the Terra are great ways to bet on this opportunity because of their technical capabilities and active development.