Stop the Bomb is a game mode. Created by Fall Out Wave.
Arena[]

The gate closed.
The arena of this game mode is mostly identical to that of 4 Teams; in each corner is a base coloured either blue, red, purple, or green. However, a new addition is a large gate in the centre of the arena, right where the Pentagon Nest is. This gate takes up roughly the space of 4 Summoners. It is indestructible, but does not do body damage. The Pentagon Nest itself is still there, but has less space to spawn Pentagons.
The Marked[]
The Marked is a special type of tank that only appears in Stop the Bomb. Similarly to a Mothership, the first 4 players who spawn in the server become Marked. However, unlike a Mothership, a Marked is functionally identical to a normal Tank, except with a large black crosshair over the main body. Players can upgrade to whatever they like, but the crosshair will always be on the tank. When a Marked dies, another player spawning in will become the new Marked.
Gameplay[]

A just-launched ICBM attacking a Marked.
Every 10 minutes, an ICBM will spawn from the gate regardless of whether other ICBMs are active or not, and will chase after the nearest Marked. If there are multiple Marked which are somehow equidistant to the ICBM(s), then it(they)will chase after the one with the higher Level or Score. The purpose of the Marked is to lure the ICBMs into enemy bases so that the ICBM will explode, and thus destroy the enemy base.
The aim of the game is to use these ICBMs to destroy enemy bases, as well as prevent your own base from being destroyed. Each base can take 3 hits from ICBMs before breaking. Upon a hit, the base of a team will visibly crack like a pane of glass. When destroyed, the base shatters and the Base Drones die, leaving the base's team defenseless. The team also cannot respawn once killed if the base is destroyed.
Strategy[]
As a Marked[]
It is recommended for a Marked to be a fast tank, like a Booster, Spike, or Annihilator, as it will be constantly chased by the ICBM. Getting a high score as a Marked is more important than as a non-Marked, as ICBMs will prioritise Marked with higher scores if there are more than two, and they are equidistant from the ICBMs.
If the Marked's base is relatively safe, then the Marked should be actively approaching the enemy bases, as the turning speed of the ICBM is not that high, and once the Marked dies to the enemy Base Protectors, the ICBM will ram into it.
As a non-Marked[]
The non-Marked play mostly similar to normal tanks in 4 Teams, except that offensive play is more encouraged. Non-marked should be escorting the Marked while they are approaching the enemy bases lest they get killed by enemy players. However, do watch out for the ICBMs following the Marked, since they will target other tanks with attacks too. Killing other Marked should also be done whenever possible, in order to prevent destruction of the friendly base.