Hi! I'm trying to find a game I used to play around 2012-2015. It was an online PvP FPS that you downloaded through a browser. There was a zombie mode that was basically like tag and some modes where your character was really small. It also had a shop where you could buy skins and weapons with in game currency, I remember it looking somewhat similar to how fortnite looks, very bright and colourful.
Source: https://www.reddit.com/r/oldgames/comments/uhmqn3/trying_to_find_an_old_online_fps_i_used_to_play/