wtf is endfield-gacha-simulator?

A9E Gacha Simulator is a browser based tool for simulating the gacha pull system in the game Arknights: Endfield. It lets players try out pulls, compare strategies, and review a full playthrough of pulls across many banners, all without needing to actually spend in game currency. The tool runs entirely offline. It does not send any data over the network, and you can switch instantly between Vietnamese and English in the interface. There are three main modes. The first lets you manually pull on character and weapon banners, doing single pulls, ten pulls at a time, or weapon specific pulls. It tracks pity counters for five star and six star items, the guarantee that protects a featured pull after a set number of tries, and other banner milestones. It also manages tickets, a system called Dossier, Bond Quota, and Arsenal, and keeps a history of past results. The second mode runs a Monte Carlo simulation, a method that runs many random trials to show an average outcome, to compare five different strategies for spending your pull resources across banners. You enter details like the number of players, number of banners, starting resources, and income per banner, then run the simulation. The results include the average number of featured pulls obtained, how efficiently tickets were used, weapon results, the rate of fully completing limited items, and a distribution chart. The third mode follows a single simulated player in detail, showing the decision to pull or skip for each banner, standard and limited pulls, changes in pity and resources, and exactly when a featured character or weapon was obtained. You can reuse the same starting seed and settings to reproduce a result. Settings and recent results are saved in the browser's local storage, and there is a reset button to restore defaults. To run it, you can either open a downloaded release file directly in a modern browser with no installation needed, or run it from source using Node.js. This is a fan made community project and not an official product from the game's developer, Hypergryph. It is meant for planning and comparison, not as a guarantee of what you will actually get from real pulls.