G Follower 3 was released during the Beta 5.3 Halloween update and is one of the first three cards to have the Future ability.
Anything with this ability activates their ability after the given turn time has come to pass. This does not count the turn it was placed. So if G Follower 3 was placed on turn 10, it would kill a random enemy monster at the start of turn 14.
G Follower 3 is particularly powerful as a solid 5/6 for 8G card. On top of its solid stats, its ability to kill a random enemy on the board regardless of whether or not this card is silenced or still alive makes it a very useful mid cost card for almost any deck.
The best part about this card is that four turns is just enough for the opponent to start building up their field, and may make them forget when the effect takes place or if it takes place at all. However, when they do remember, it can backfire on you if they place a lonely Mettaton NEO for the GF3 to kill.