[JustBored]

You have to make a variable (global) for example, g_Worls and when 2 players start dueling put 1 more point to the variable. I know i havent explain very well here is an example:

pawn Код:

new g_World;
g_World = 10; //the starting virtual world
CMD:accept(playerid, params[])
{
    new string[128];
    if(IsInDuel[playerid] == 1) return SendClientMessage(playerid, COLOR_RED, "You Are Already in Duel!");
    if(Dueler[playerid] == 0) return SendClientMessage(playerid, COLOR_RED, "No one has sent you a Duel Request.");

    format(string, sizeof(string), "** %s (%d) Has Accepted Your Duel Challenge.", GetName(playerid), playerid);
    SendClientMessage(Dueler[playerid], COLOR_ORANGE, string);
    format(string, sizeof(string), "You've Accepted %s (%d) Duel Challenge!.", GetName(Dueler[playerid]), Dueler[playerid]);
    SendClientMessage(playerid, COLOR_LIGHTBLUE, string);

    format(string, sizeof(string), "The Duel Between %s and %s Has Started!", GetName(Dueler[playerid]), GetName(playerid));
    SendClientMessageToAll(COLOR_ORANGE, string);
    
    new Float:x, Float:y, Float:z;
    GetPlayerPos(playerid, x, y, z);
    GetPlayerPos(Dueler[playerid], x, y, z);
    SetPlayerInterior(playerid, 16);
    SetPlayerInterior(Dueler[playerid], 16);
    SetPlayerVirtualWorld(playerid, g_World);
    SetPlayerVirtualWorld(Dueler[playerid], g_World);
    g_World ++;
    SetPlayerPos(playerid, -1395.067, 1261.3706, 1042.8672);
    SetPlayerPos(Dueler[playerid], -1395.067, 1261.3706, 1042.8672);
    SetPlayerHealth(playerid, 100.0);
    SetPlayerHealth(Dueler[playerid], 100.0);
    SetPlayerArmour(playerid, 100.0);
    SetPlayerArmour(Dueler[playerid], 100.0);
    IsInDuel[playerid] = 1;
    IsInDuel[Dueler[playerid]] = 1;
    return 1;
}