run with php -d memory_limit=4048M parse.php

parse.php

<?php
//ini_set('memory_limit','4GB');

$pages = 30;
$size = 10000;
$total_games = 0;
$factions = [1 => [], 2 => [], 3 => [], 4 => [], 5 => [], 6 => []];

$players_by_game = [];

for ($p = 1; $p <= $pages; $p++)
{
	echo date('Y-m-d H:i:s') . ": Page $p of $pages\n";
	//$json = file_get_contents("https://api.faforever.com/data/gamePlayerStats?sort=-id&include=player&page[size]=${size}&filter[gamePlayerStats]=score%3E0&page[number]=${p}");
	$json = file_get_contents("https://api.faforever.com/data/gamePlayerStats?sort=-id&include=player&page[size]=${size}&page[number]=${p}&filter[gamePlayerStats]=score!=0");
	$arr = json_decode($json, true);	

	foreach ($arr['data'] as $k => $v)
	{
		$fac = $v['attributes']['faction'];
		if (empty($factions[$fac]))
		{
			$factions[$fac] = ['wins' => 0, 'games' => 0, 'players_ids' => []];
		}
		$game_id = $v['relationships']['game']['data']['id'];
		
		if (empty($players_by_game[$game_id]))
		{
			$players_by_game[$game_id] = [];			
		}
		$players_by_game[$game_id][] = $fac;
		
		$player_id = $v['relationships']['player']['data']['id'];
				
		if ($v['attributes']['afterDeviation'] < 200 && $v['attributes']['afterMean'] > 1000 && $v['attributes']['beforeMean'] > 1000)
		{		
			if ($v['attributes']['score'] != 0)
			{				
				$is_win = ($v['attributes']['score'] > 0);
				$scoreTime = $v['attributes']['scoreTime'];				
				$factions[$fac]['games']++;
				if (!isset($factions[$fac]['players_ids'][$player_id]))
				{
					$factions[$fac]['players_ids'][$player_id] = ['games' => 0, 'wins' => 0];
				}
				
				
				if (empty($factions[$fac]['game_ids'][$game_id]))
				{
					$factions[$fac]['game_ids'][$game_id] = ['plays' => 0, 'wins' => 0];
				}

				$factions[$fac]['players_ids'][$player_id]['games']++;
				if ($is_win)
				{
					$factions[$fac]['wins']++;					
					$factions[$fac]['game_ids'][$game_id]['wins']++;
					$factions[$fac]['players_ids'][$player_id]['wins']++;
				}
				else
				{
					
				}
				$factions[$fac]['game_ids'][$game_id]['plays']++;
				
				if ($fac >= 1 && $fac <= 4)
				{
					$total_games++;
				}
			}
		} else
		{
			if (empty($factions[$fac]['small_rating']))
			{
				$factions[$fac]['small_rating'] = 0;
			}
			$factions[$fac]['small_rating']++;
		}
	}	
}

//var_dump($players_by_game);

// nomads ?
unset($factions[5]);
unset($factions[6]);

function cmp($a, $b) {
    if ($a['games'] == $b['games']) {
        return 0;
    }
    return ($a['games'] < $b['games']) ? 1 : -1;
}

// filter-out non-ladder
foreach ($factions as $fac => $row)
{
	foreach ($row['game_ids'] as $game_id => $result_row)
	{
		if (count($players_by_game[$game_id]) > 2)
		{
			$factions[$fac]['games']-= $result_row['plays'];
			$factions[$fac]['wins']-= $result_row['wins'];
			$total_games-= $result_row['plays'];
			
			if (empty($factions[$fac]['non_1x1']))
			{
				$factions[$fac]['non_1x1'] = 0;
			}
			
			$factions[$fac]['non_1x1']++;
		}
		else if (count($players_by_game[$game_id]) == 2)
		{
			$found = false;
			$other_fac = null;
			$game_factions = $players_by_game[$game_id];
			for ($i = 0; $i < 2; $i++)
			{				
				// ignore nomads
				if ($game_factions[$i] > 4)
				{
					$other_fac = null;
					
					if (empty($factions[$fac]['nomads_data']))
					{
						$factions[$fac]['nomads_data'] = 0;
					}
					
					$factions[$fac]['nomads_data']++;
					
					$factions[$fac]['games']-= $result_row['plays'];
					$factions[$fac]['wins']-= $result_row['wins'];
					$total_games-= $result_row['plays'];
					
					break;
				}
				if ($game_factions[$i] == $fac && !$found)
				{
					$found = true;
				} else {
					$other_fac = $game_factions[$i];
				}
			}
			
			if ($other_fac)
			{
				if (empty($factions[$fac]['games_vs']))
				{
					$factions[$fac]['games_vs'] = [1 => 0, 2 => 0, 3 => 0, 4 => 0];
				}
			
				if (empty($factions[$fac]['wins_vs']))
				{
					$factions[$fac]['wins_vs'] = [1 => 0, 2 => 0, 3 => 0, 4 => 0];
				}
				
				$factions[$fac]['games_vs'][$other_fac]++;
				if ($result_row['wins'])
				{
					$factions[$fac]['wins_vs'][$other_fac]++;
				}
			}			
		} else
		{
			if (empty($factions[$fac]['inc_data']))
			{
				$factions[$fac]['inc_data'] = 0;
			}
			$factions[$fac]['inc_data']++;
		}
	}
		
	$factions[$fac]['players_cnt'] = count($factions[$fac]['players_ids']);
	
	uasort($factions[$fac]['players_ids'], "cmp");
	
	$factions[$fac]['players_ids_top_games'] = array_slice($factions[$fac]['players_ids'], 0, 10, true);
	foreach ($factions[$fac]['players_ids_top_games'] as $p_id => $row)
	{
		$factions[$fac]['players_ids_top_games'][$p_id]['winrate'] = $row['wins'] / $row['games'];
		unset($factions[$fac]['players_ids_top_games'][$p_id]['wins']);
	}
	
	unset($factions[$fac]['players_ids']);
	
	$factions[$fac]['game_ids_cnt'] = count($factions[$fac]['game_ids']);
	unset($factions[$fac]['game_ids']);
}

foreach ($factions as $fac => $row)
{
	foreach ($factions[$fac]['wins_vs'] as $other_fac => $val)
	{
		$factions[$fac]['wins_vs'][$other_fac] = $val / $factions[$fac]['games_vs'][$other_fac];
	}
}

echo "LAST entry time:" . $scoreTime . ", games - $total_games \n";

foreach ($factions as $i => $val)
{
	$factions[$i]['win_pct'] = $factions[$i]['wins'] / $factions[$i]['games'];
	$factions[$i]['usage_pct'] = $factions[$i]['games'] / $total_games;
}

echo json_encode($factions, JSON_PRETTY_PRINT);