Unfortunately, a refund in such cases (even if supposed mishaps) is not possible.
The most you can do is be a tad bit more careful in the future.

For any payment-related inquiries, it's best if you contact the Tech Support - only they can know for certain.

Once completed, the rewards of special missions have to be claimed before they officially end with the event, otherwise their reward after completion will disappear together with them once the available time for completing them officially runs out, so be careful and don't hold on to them, but rather claim them immediately once finished.
 
Yes, they do. You have to manually claim them each day of an active Premium account.

Premium Account (which there's an abundance of currently) [possibly combined with the Beginner's Pass as well, depending on the player's rank], increased battle funds, tons of special April Fool's gold boxes with an increased drop-rate, only playing in the special DM holiday mode, missions.. etc.
Super simple.

Hi!
For any payment-related inquiries, it's best if you consult with the Tech Support by contacting them via this form — only they can help you with such matters.

Special missions can only be accessed in the HTML5 (either on browser or the official HTML5 client) and Android mobile version of the game.

All of the information regarding the April Fool's sales can be found in the official announcement thread.
 
 

Hunter's OD has received changes as per the Patch Update #594.
 
If you'd like to continue this discussion, you can do so in either of the two topics:
Let's discuss Hunter! Let's Discuss Overdrives  
Thread closed.

To leave a battle group in the HTML5 version of the game, simply left-click on your nickname at the very top-left side of the game's interface and select the 'Leave group' option from the drop-down menu:

Both the Deathmatch (DM) [matchmaking only] and Juggernaut (JGR) modes have been removed from the game, and JGR has been replaced with Team Juggernaut (TJR).
Both of the removed game modes may still reappear during special occasions and major events for a limited amount of time.

Note: The official announcement has just been released: Fool Days 2020

Hey!
After a certain period of inactivity — depending on the player's rank and whether or not they've made an in-game Shop purchase (which automatically protects the account's nickname from re-registration for an additional minimum period of 3 years following the date of the last purchase (regardless of the player's rank)) — an account's nickname may become re-available for registration again. This system has been put in place in order to free-up nicknames of inactive accounts for other active players to be able to use.
Important: Do note that after an inactive account has its nickname taken by someone else, it will NOT be lost (or have any of its data related to it prior to the period of inactivity changed) or assigned to a new player, but merely receive a new nickname with the prefix 'r_' in front of it — so if an account was for example named 'Tanker', it'll have its nickname automatically changed by the system to either  'r_Tanker' or 'r_Tanker0', in case 'r_Tanker' has already been taken.
If your account's nickname has been changed due to inactivity (meaning that someone else has re-registered it), you can choose a new nickname for your account (free of cost) by contacting the Tech Support via this form. Before choosing a new nickname for your account, make sure to check its availability.
 
Additionally, you can learn more about nicknames and the system surrounding them in more detail on their official Wiki page.

[Duplicate question]:
 

Keep an eye out on the N&A section.

You're required to visit the «Special» tab in the missions section (either on the HTML5 or mobile version of the game) prior to starting, otherwise your progress toward the mission won't count. Do note that the special mission can only be completed in regular matchmaking, non-PRO battles.

Hey.
Kindly put those players who bother you on your ignore list (either by left-clicking on their nickname and selecting the 'Ignore' option, or by using the /block Nickname chat command) and you won't see their messages ever again. If a moderator happens to be present in the chat at the time, they will deal with the violator accordingly.
Additionally, if you'd ever like to raise your concerns regarding a certain player's behavior, you can always contact a Chat Administrator (@Hate or @Defender) via Forum PM.

Nothing. You (or someone else on your account if it has been accessed unlawfully) violated the game rules and received a punishment. In case you believe you didn't violate the game rules, you can contact the Tech Support and they will look into it and decide whether or not the account block will remain.

Problem solved.
 
In the future kindly follow the respective contest announcement threads.

Efficiency (/ effectiveness rating) is calculated using a complex formula which has not been disclosed by the Developers. It is supposed to reflect how effective you are in battles.

If someone believes they've either been punished unfairly or by mistake, they can always contact a chat administrator (depending on the locale in which the ban was issued) via Forum PM to resolve the matter.
However do note that chat mods are very well-trained and experienced (most with many years on the job), so the possibility of such an instance occurring is very unlikely.
 
Thread closed.

Hey.
Kindly put those players who bother you on your ignore list (either by left-clicking on their nickname and selecting the 'Ignore' option, or by using the /block Nickname chat command) and you won't see their messages ever again. If a moderator happens to be present in the chat at the time, they will deal with the violator accordingly.
Additionally, if you'd ever like to raise your concerns regarding a certain player's behavior, you can always contact a Chat Administrator (@Hate or @Defender) via Forum PM.

The chance of a gold box dropping has been disclosed by the Developers to be at around 1/3 (/ 33.33%) or 1/1260 per second, as it's connected to the battle timer now. You can learn more about gold boxes here.

To exit your account, simply click on the red 'X' button located at the very top-right corner of the client and log out from there. Additionally, if that would for whatever reason not work, you could also clear your client's cache, which would clear all of the login details and therefore automatically log you out of the account and meet you with the login screen upon re-opening the client.

Hello, are you referring to joining the YouTuber TO program (which also rewards containers to its members based on their monthly YT views)?

Please see my post here.