Hardest Hollow Knight bosses

59 ELO points separate Grimm Troupe Master from Radiance at the top of the Hollow Knight boss difficulty ranking, after 5008 duels.

Radiance, perched at 1499 ELO, trails Grimm Troupe Master by a single point yet sits 59 points above third-place Mantis Lords. This sharp drop from rank 2 to rank 3 reveals how players single out the top duo as a tier apart in challenge. Grimm Troupe Master, with 183 duels and a 70% win rate, claims the summit by the narrowest margin, while Radiance boasts a 78% win rate across 143 duels, the highest consistency in the top five. Broken Vessel rounds out the top five at 1347 ELO, still 348 points clear of the bottom. At rank 28, Gruz Mother languishes at 945 ELO with a 26% win rate, underscoring the community's view of early-game encounters as mild warm-ups compared to the endgame gauntlet.

This ranking draws on 5008 duels cast by 56 players across 28 bosses, capturing the full spectrum of Hollow Knight's combat trials. Updated on 11 October 2026, the list reflects live player opinion on which fights truly tested their limits. Cast your own votes to reshape the hierarchy and make your toughest battle count.

Updated on October 11, 2026

How this ranking is computed

Every duel won lifts a contender and every loss drops them, by an amount that depends on the opponent's strength: beating the leader is worth more than beating the last. It is an ELO, the same principle as in chess. Duels are not drawn at random — an adaptive entropy sort puts the least predictable match-ups first, which settles the ranking far faster than a full round robin. A worldwide ranking is only published past 30 completed plays. Known limit: a contender who has faced few opponents keeps an approximate score, and the bottom of the table moves more than the podium.

How our rankings are made →