This Is Not A Test is a skirmish miniature game with a post-apcolyptic theme.

The website notes:

Greetings wastelanders! If you’re just tuning in, my name is Johnny Atom-Bomb, your humble host broadcasting live from Old Line Radio, the Tri-State Wasteland’s only radio station, excepting derelict government civil defense broadcasts or other dubious transmissions. The wasteland may not look like much, but she’s all we got, and I’m here to help you see another sunset. So load your gun, turn up that dial, and stay tuned.”

—Old Line Radio Opening Sign-on Announcement

The rules of TNT could be used for any post-apocalyptic world, but the official setting begins in the heart of the Tri-State Wasteland, a part of the old Mid-Atlantic States of Maryland, Pennsylvania, and West Virginia.
The core rules include, from website "This is Not a Test uses 10-sided dice, referred to as D10 in the rules, and occasionally standard six-sided dice, labeled D6.

Two types of dice roll mechanics resolve all actions: Opposed and Stat tests.

Opposed tests are used for resolving direct actions between figures, mainly close combat. Both players roll a D10 and add the appropriate stat and any applicable modifiers. The highest score wins. Ties always go to the defender.

Stat tests are used when a figure is trying to accomplish an action, usually something unopposed by an enemy model. Examples include opening a locked door or climbing a ledge. The player rolls a D10, adds the relevant stat and any applicable modifiers, and checks to see if he rolled equal to or higher than the required Target Number (TN). The TN is specified by the type of action, as are the results of success or failure. Unless otherwise specified, all stat tests have a TN of 10. Specific types of tests are discussed further under stats.

Additionally, several dice conventions are used.

Critical Hit: A natural roll of 10 on the D10 indicates a lucky bonus. Should a Critical be scored the player may roll a D6 and add the result to their original D10 roll.

Fumble: A natural roll of 1 is always bad, but does not result in any penalties. However, 1s cause additional problems, such as weapon failure or ammo depletion, which are described later in the relevant sections.

D3 – Some rules require the roll of a D3. To get a result roll a D6, where a score of 1 to 2 = 1, 3 to 4 = 2, and 5 to 6 = 3. Rolling a D3 never results in a Critical or Fumble.

Scatter – Scattering means to determine a random direction, usually to represent a misplaced grenade or errant entity. To determine this direction simply roll a scatter die, or if that is unavailable, roll D10 and use the direction the top of the die is pointing, or some other agreed upon method.

Rerolling Dice – Some abilities allow players the opportunity to reroll their dice in the event they are unhappy with the first result. The second result cannot be rerolled even if it is worse. You may not reroll a reroll!"

The game will offer random encounters to give the play a different feel.

"In This Is Not a Test your warband’s problems don’t just start with your opponent, the wasteland itself can be just as danger. TNT offers rules for both hazards of wastes as well as a bestiary of wasteland denizens. At the beginning of each battle, players roll to determine if any hazards are present. There roughly a 50% chance something bad will occur. The point was to offer something a little different without over burdening the players with too much going on.

"Hazards are natural, and unnatural, phenomena that pervade the wasteland. Earthquake, ash storms, unexploded ordinance and other dangerous events. Below are just two examples taken directly from TNT."

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