Best Karthus ADC Synergies

The best Support with Karthus ADC is Nautilus. The pair wins 55.4% across 1,631 games, 0.9 points more than the two champions' own win rates predict. Leona (+0.7 over 1,325 games) and Senna (+0.5 over 1,014 games) also over-perform. Leona has the highest raw win rate (58.1%) among well-sampled pairs, but that is about what its own strength predicts (55.9% expected). Based on High Elo Ranked Solo/Duo games, patches 26.20-26.22. These are observed associations, not guaranteed outcomes. The weakest listed synergies for Karthus ADC are Lee Sin Jungle. The detailed info below lists each partner with observed win rate, expected win rate delta, sample size, rank scope, and patch window.

Updated 2026-11-15. Data is current for LoL patch 26.22 (all regions, low elo and high elo).

Top 4 High Elo Karthus ADC bot-lane duo synergies with Support

  1. Nautilus Support - 55.4% win rate with Karthus ADC (+0.9 points vs expected), 1,631 games.
  2. Leona Support - 58.1% win rate with Karthus ADC (+0.7 points vs expected), 1,325 games.
  3. Senna Support - 55.2% win rate with Karthus ADC (+0.5 points vs expected), 1,014 games.
  4. Nami Support - 56.1% win rate with Karthus ADC (+0.3 points vs expected), 1,779 games.

Top 8 High Elo Karthus ADC all-role strongest synergies

  1. Yasuo Mid - 55.2% win rate with Karthus ADC (+1.2 points vs expected), 1,169 games.
  2. Nautilus Support - 55.4% win rate with Karthus ADC (+0.9 points vs expected), 1,631 games.
  3. Zed Mid - 57.9% win rate with Karthus ADC (+0.8 points vs expected), 1,253 games.
  4. Leona Support - 58.1% win rate with Karthus ADC (+0.7 points vs expected), 1,325 games.
  5. Yone Mid - 56.2% win rate with Karthus ADC (+0.7 points vs expected), 1,298 games.
  6. Graves Jungle - 57.3% win rate with Karthus ADC (+0.5 points vs expected), 1,096 games.
  7. Senna Support - 55.2% win rate with Karthus ADC (+0.5 points vs expected), 1,014 games.
  8. Nami Support - 56.1% win rate with Karthus ADC (+0.3 points vs expected), 1,779 games.

Top 1 High Elo Karthus ADC all-role weakest synergies

  1. Lee Sin Jungle - 51.3% win rate with Karthus ADC (-0.1 points vs expected), 1,192 games.

How these matchup statistics are calculated

Counter and synergy statistics use Ranked Solo/Duo games, exclude matches shorter than 600 seconds, and group results by patch window, region, rank scope, and champion role.

Pairwise pages use a rolling three-patch window and compare observed win rate with a log-odds expected win rate based on each champion's role-adjusted baseline; listed pairs require at least 1,000 games.

Read the full methodology for the model and guidance on interpreting these results.