Back to the Future
From Worms Knowledge Base
Upon selection, your worm produces what appears to be a modified teleport. Modified it is, because it's no ordinary universe-folding instrument. This teleport allows your worm to jump into the future. Once selected, simply click somewhere else on the map and your worm will vanish out of sight. A few turns later, he will appear at the designated location for a surprise attack on the enemy.
The number of turns that expire before your worm re-enters the timeline can be determined using the numbers 1-9 on the keyboard, and the location remains secret to all other players until your worm shows up.
During his absence, the worm's details would have to be stored for later retrieval, as with the Alien Abduction weapon. The game would also have to remember when to bring the worm back into the game. The worm would have to be made exempt to worm select. The worm's return could occur on his turn or on another worm/player's turn, this would depend on the player's choice of how many turns expire before the worm comes back.
If the terrain has deformed and the worm is unable to enter the game at the chosen location, a force-teleport could be made to the nearest available space.
If you're good with your predictions you can use this weapon for a great strategical advantage. This would be similar to a teleport which doesn't use your turn up - you could teleport to the enemy and attack before he has a chance to react. Except using this weapon in such a fashion requires that the enemy worm still be there when you pop back into the timeline - and if the landscape has changed, or a mine has been displaced, it's a risky move. Then again, keeping your worm outside the game for a short period prevents him from sustaining any damage - you could use this weapon in conjunction with the Scales of Justice or the Indian Nuke, by avoiding global damage or poison that these weapons bring.
The weapon isn't really time travel as such unless the 'time-travelling' worm experiences no aging during the jump - and that's hard to tell. But advertising this weapon as a time-travel device could be what sells it, since time-travel is the unlikely concept that should fit well into Worms. The weapon is also asking for some fancy visual effects.