Sum Link is a puzzle game designed to train mathematical and logical skills. In this game, you will encounter a grid with various numbers distributed across it. Your objective is to connect these numbers in a way that the sum of each connected line equals the given target number. Each connection must be a straight line and cannot overlap or cross. Regular numbers can only be connected once, but special numbers can act as intersections, allowing multiple connections.

Game Rules:
1. Number Grid: At the beginning of each level, you will face a grid composed of squares, each labeled with a number. These numbers will be the objects you'll connect during the game.

2. Target Numbers: In each game level, you will receive several target numbers. Your goal is to connect the numbers on the grid in a way that the sum of each connected line equals the target number.

3. Connection Rules: When connecting numbers, you must follow these rules:
- Connections must be straight lines, either horizontally, vertically, or diagonally.
- Lines cannot overlap or cross, and each square can only be connected by one line.
- Regular numbers (non-special numbers) can only be connected once.
- Special numbers can act as intersections, allowing multiple connections.

Game Objective:

The primary objective of Sum Link is to help players exercise their mathematical calculation and logical thinking abilities. By solving various mathematical problems and strategizing with the use of special numbers, players will continuously challenge their mathematical skills and develop problem-solving capabilities. Additionally, the game aims to spark players' interest in mathematics, making the learning of math more enjoyable and engaging.