Gain insights into Solidity fundamentals, the Ethereum network, and blockchain basics. Learn about creating and deploying Play-to-Earn games, overcoming technical challenges, and earning cryptocurrency rewards.

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Ethereum

Default

Solidity is a high-level programming language used for implementing smart contracts. Solidity is widely-used in developing Play-to-earn (P2E) games. P2E are NFT-gated games on the blockchain, where players can earn cryptocurrency and prizes that have real-world value. The ability to make these games is currently one of the most sought-after skills among blockchain developers.

In this course, you will be introduced to Solidity and the fundamentals of the Ethereum network. This course also gives a preliminary introduction to blockchains so users who don’t have any prior knowledge of it can brush up on their concepts—to assist them in developing and deploying P2E smart contracts in Solidity. Next, this course will also address a few technical challenges that P2E games present. 

By the end of this course, you will be able to create and deploy your own P2E game on an Ethereum test network.

Developing Play-to-Earn Games in Solidity

```s
npm install @openzeppelin/contracts
```

import "@openzeppelin/contracts/access/Ownable.sol";
pragma solidity >=0.4.0 <0.7.0;
contract X is Ownable{}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)

pragma solidity ^0.8.0;

/**
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes calldata) {
        return msg.data;
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (access/Ownable.sol)

pragma solidity ^0.8.0;

import "./Context.sol";

/**
 * @dev Contract module which provides a basic access control mechanism, where
 * there is an account (an owner) that can be granted exclusive access to
 * specific functions.
 *
 * By default, the owner account will be the one that deploys the contract. This
 * can later be changed with {transferOwnership}.
 *
 * This module is used through inheritance. It will make available the modifier
 * `onlyOwner`, which can be applied to your functions to restrict their use to
 * the owner.
 */
abstract contract Ownable is Context {
    address private _owner;

    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    constructor() {
        _transferOwnership(_msgSender());
    }

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        _checkOwner();
        _;
    }

    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view virtual returns (address) {
        return _owner;
    }

    /**
     * @dev Throws if the sender is not the owner.
     */
    function _checkOwner() internal view virtual {
        require(owner() == _msgSender(), "Ownable: caller is not the owner");
    }

    /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions anymore. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby removing any functionality that is only available to the owner.
     */
    function renounceOwnership() public virtual onlyOwner {
        _transferOwnership(address(0));
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Can only be called by the current owner.
     */
    function transferOwnership(address newOwner) public virtual onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        _transferOwnership(newOwner);
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Internal function without access restriction.
     */
    function _transferOwnership(address newOwner) internal virtual {
        address oldOwner = _owner;
        _owner = newOwner;
        emit OwnershipTransferred(oldOwner, newOwner);
    }
}

// SPDX-License-Identifier: MIT
import "./Ownable.sol";
pragma solidity >=0.6.0 <0.9.0;
contract X is Ownable{}


Safely control and transfer ownership of your smart contract.

Introduction

Ethereum Fundamentals

Solidity Smart Contract Structure and Syntax

Inheritance

Off-Chain Oracles

Putting it All Together: The Treasure Hunt Game

Conclusion

Ownability

OpenZeppelin