What board game would you recommend to someone who only knows chess and wants to try something modern

[BiscuitTin]

My dad is 62, has played chess seriously for 40 years and finds most board games too simple. He has asked me to recommend something modern that might challenge him in a different way. He enjoys deep strategy, does not mind complexity and has patience for longer games. He is sceptical of anything with dice or luck elements. What would you recommend?

[StormForge62]

Hive is the immediate answer for a chess player who wants zero luck and pure abstract strategy. Two players, no board, tiles placed and moved with specific movement rules, the goal is to surround the opponent's queen bee. The strategic depth rewards the kind of positional thinking chess develops and there is no randomness whatsoever

[Ruby92]

Through the Ages: A New Story of Civilisation for a civilisation building card game with the strategic depth of chess in a very different format. No map, pure resource and development decisions, long-term planning essential. Genuinely one of the most complex and rewarding modern board games available

[SortedMate]

Twilight Imperium 4th Edition is the long-game answer if he has the patience and the group. Six to eight hours, 3-6 players, galactic empire building with genuine diplomatic, military and economic strategy. The complexity is enormous and the chess-like calculation of multiple players' intentions simultaneously is exactly the kind of challenge a serious chess player finds interesting

[VidiTechnica]

Terra Mystica or Gaia Project for a solo or two-player deep strategy experience. Engine building, resource management, asymmetric factions with completely different abilities and the kind of long-term planning horizon that rewards strategic thinking over tactical improvisation. No luck elements

[QubitZero13]

Pandemic Legacy Season 1 is the exception to the no-luck preference worth making a case for. The campaign structure and the evolving narrative add a dimension that pure abstract games cannot. Chess players who try legacy games sometimes find the narrative uncertainty more interesting than they expected. Worth mentioning as a counter-recommendation

[Jan79]

Go is the recommendation if he genuinely wants to be humbled by a game with more strategic depth than chess. The ruleset is simpler than chess but the strategy is considered more complex. If he has never played Go and considers himself a serious chess player, Go is the challenge that might genuinely fascinate him