Racing 92 are the favourites to progress from Pool 1 as they look to go one better following last season's final defeat to Saracens.
Ronan O'Gara won two European Cups with Munster and the Racing coach comes up against his former side on Sunday, live on Sky Sports 2. The Irish province are still adjusting to life under director of rugby Rassie Erasmus and suffered a disappointing defeat to rivals Leinster last weekend.
Leicester Tigers are gunning for Racing following last season's semi-final loss to the Parisians while Gregor Townsend is targeting the knockout stages in his final season as Glasgow coach.
Racing 92
Champions Cup record: P40 W18 D3 L19
Best finish: Runners-up (2015-16)
What's hot: Racing are playing entertaining, attacking rugby with Dan Carter at the forefront, while Juan Imhoff has started the season in red-hot form. They boast serious strength in depth and are targeting Europe after last season's disappointing final defeat to Saracens.
What's not: Just 57 days separated Racing's Top 14 final win and the opening game of this season. That lack of downtime and the fitness concerns over Carter have been factors in the Parisians' inconsistent start to the season.
What's changed: Leone Nakarawa has filled the second row slot vacated by Luke Charteris and the Fijian star will have Racing fans on the edge of their seats.
One to watch: Juan Imhoff has scored seven tries is six appearances this season and will look to continue that form in Europe.
Glasgow Warriors
Champions Cup record: P103 W34 D2 L67
Best finish: Quarter-final play-offs (1997-98)
What's hot: Glasgow's squad is awash with international experience and their backline in particular have the ability to terrorise teams.
What's not: Nakarawa's absence will be sorely felt. To make matters worse, Glasgow must try and contain the brilliant Fijian in December when they face Racing twice in the space of seven days.
What's changed: Former All Blacks hooker Corey Flynn and Italy wing Leonardo Sarto have joined the club, while head coach Townsend is taking over the Scotland national team at the end of the season.
One to watch: Stuart Hogg has his sights set on a Lions starting place and has started the season in blistering form. Glasgow need him to replicate that on the European stage.
Leicester Tigers
Champions Cup record: P138 W90 D5 L43
Best finish: Winners (2000-01, 2001-02)
What's hot: The Tigers remain strong in the set piece and have one of the best lineouts in the Premiership. Owen Williams is kicking at over 85 per cent off the tee and Peter Betham has shone since moving from the wing to centre.
What's not: When Leicester last won the European Cup in 2002 they conceded just five tries in nine matches. Those days of defensive resilience are a distant memory at the moment. They have shipped 16 tries in six fixtures this season, conceding over 30 points in three of those games and it resulted in the sacking of defence coach Scott Hansen last week. Discipline has also been an issue, conceding an average of 10 penalties per game.
What's changed: Southern hemisphere stars Matt Toomua and JP Pietersen have moved to Welford Road while Vereniki Goneva, their joint-top try scorer last season, has joined Newcastle Falcons.
One to watch: Telusa Veainu is a constant threat with ball in hand and scored a stunning try against Worcester last Saturday, punishing a loose kick downfield.
Munster
Champions Cup record: P150 W103 D1 L46
Best finish: Winners (2005-06, 2007-08)
What's hot: Erasmus has yet to get the best out of Munster but they have still ground out four victories in their opening six Guinness PRO12 games. The return of skipper Peter O'Mahony from a long-term injury is a massive boost and adds further depth to their back row, while Darren Sweetnam's form has been noticed by Joe Schmidt.
What's not: Munster can sometimes struggle to break teams down and will require a lot more than one-out runners against the cream of Europe. They are over-reliant on Conor Murray and their midfield remains a work in progress.
What's changed: Erasmus has taken over as director of rugby, with Anthony Foley remaining as head coach. Johnny Holland was forced to retire due to hamstring injuries while BJ Botha moved to France. Jean Kleyn, Jaco Taute, Rhys Marshall and Thomas du Toit have arrived from Super Rugby.
One to watch: Tyler Blyendaal has been dogged by injuries since joining from the Crusaders in 2014 but he has got a run of games under his belt this season and could be the solution to Munster's fly-half problems.