Basic positioning for 4v4 Haxball

GK=goalkeeper
DM=defensive midfielder
AM=advanced midfielder
ST=striker

when talking about attacking situations I'm only referring to the most common scenario, where the attacking team has a player in the corner.

the DM should kick at the start, with the AM and ST at opposite sides.

GK
when defending the gk should remain in its goal, glued to the first goalpost. that means, in particular, not confronting the opponent at the corner (when the gk finds itself there, say because it went there to protect the ball during a counterattack, it should stall for time and let the DM/AM take over as soon as possible, going to the first goalpost). this is because a defender that manages to stop an attack in the corner will often be advancing and starting a counterattack, an offensive role that's outside the gk's scope.

when the ball is in the midfield the gk should keep central, and just enough behind the opponent ST that it can defend a counterattack. it's a false impression that the more behind the gk stays, the safer: counterattacks are stopped more easily when they're just starting, as opposed when they're fully developed in a 2vs1 scenario, and as long as the gk is between its goal and the opponent it's already perfectly safe. plus, if the gk advances it gives its teammates another passing target, and in general it can partecipate in getting the ball forward.

when attacking, the gk should be central, in line with the first goalpost, such that it can contribute to shifting the ball from side to side. a typical scenario is player A in the corner backpassing to B, probably the DM. the GK should make itself available in the center to receive a pass from B and transfer the ball to D on the other corner.

DM
when defending the DM should be right next to the GK, and like the GK shouldn't go fight for the ball in the corner (*).

in the remaining situation, a good rule of thumb is that the DM should pretend to be a GK in a 3v3 game: in particular when on the offensive, it should go behind the teammate in the corner to receive a backpass.

AM
when defending the AM should be the one to fight for the ball in the corner (*).

when attacking the AM is functionally identical to the ST.

ST
when in defense the ST should position itself where it's most probable that it can receive the ball if its teammates manage to disengage. in regulated 4v4 matches the ST is prohibited to partecipate in the defense, but in a casual scenario there's nothing wrong with retroceding occasionally to contest a ball.

when attacking, the ST is either the player in the corner, from where it can backpass or cross, or the player ready to receive the cross, usually in the neighborhood of the second goalpost and leaving a fair bit of room between it and the goal, both because the opponent GK+DM make tight crosses impossible and because it should accelerate towards the goal a bit when the cross happens.


(*): depending on the situation, if the DM is positioned to go after the ball in the corner, it can do so, with the AM covering the position next to the GK.