Think of DeFi as a financial system built in the cloud, and oracles are the only bridge connecting reality with the blockchain. In 2025, an era of fragmented liquidity and fierce competition among various Layer2 solutions, many still cling to old perceptions—thinking that feeding prices is just about dumping some major exchange's market data onto the chain. In reality, each price update is a delicate balance in a millisecond-level game.

To understand oracles, one must first grasp the biggest blind spot in blockchain—its blindness to the outside world. Smart contracts are like accountants who never leave their offices; they keep accurate ledgers but know nothing about the outside environment. Lending protocols need real-time ETH prices to determine whether to liquidate positions, and this is where oracles come into play. The problem is: if manipulating a price can earn a hacker one hundred million dollars, and the cost of attack is only ten million, rational hackers will definitely strike.

This involves the classic concept from game theory—the Schelling point. A group of distrustful individuals will naturally focus on the most obvious answer. For oracle nodes, the true price is that focal point. Most nodes report the real price; if you report a false price, you not only get no reward but also risk losing your staked collateral. This honest mechanism, built on economic incentives, underpins the foundation of on-chain finance.

By 2025, the oracle battlefield has long since upgraded. It’s no longer just about accuracy but revolves around OEV—Oracle Extractable Value. Whoever can control the timing of price information release gains hidden arbitrage power. This is the key battleground of the next phase.