Omega Strikers is a F2P Sports game and can be described as a 3v3 air hockey game with abilities.

The main objective of the game is to outsmart your rivals and score a certain amount of points to win the match. The amount of points to score differs from gamemode. Before scoring a point, there are some parts of the arena where the ball must hit first, after doing that, the gate which defends the goal opens and makes the opponents more vulnerable. At the beginning of each match, you choose your character with certain abilities. Each character's ability adds variety to each game. Before the match, after choosing your character, you also choose a buff, adding an additional bonus to the role you play. There are two roles, two forward players and one goalie. Choosing the right character for each role can be crucial to the outcome of the match.
Apart from abilities, you have different arenas, which differs by only the parts which must be hit before the goal become defenceless. Apart from that, you only have three gamemodes.
There are not many obligatory microtransactions for a F2P game to be honest, which is good, mostly fashion items, but the important thing are the characters, who can be bought with currency earned by simply playing the game.