It may vary from country to country, but in general it has several parts:
1) Panel discussion with a case
Panel discussion is aimed to check how well you work in a teams. Try to be nice and not push too hard. Leverage your industry eperience and case prep experience. Feel free to contact me for panel case prep
2) Market-sizing exercises on paper
Standard marketsizing cases, so make sure you prep for it.
3) 1-2 One-on-one interviews with managers that include case + fit. May be on a same or different day depending on their capacity.
One-on-one interviews are less formal and structured than in Big 3. 40% chance - marketsizing, 40% profitability, 20% standard market, company competitors, etc. framework. So prioritize your prep efforts accordingly. Also be ready for fit: Tell me about yourself, why consulting, why Accenture, leadership story, teamwork story, your questions to them