Mars vs Phantom Assassin

How this matchup plays

Trapping an enemy inside Arena of Blood is the foundation of Mars's teamfight, but Phantom Assassin almost completely ignores it. She can use Phantom Strike on any allied or enemy unit outside the walls to escape instantly, turning his signature ultimate into a minor obstacle. Even before that, her Blur gives her a chance to evade Spear of Mars, which can ruin his initiation before it even starts. Mars relies on physically pinning enemies down, but Phantom Assassin's mobility and evasion mean she rarely has to play by his rules.

This dynamic makes it very difficult for Mars to do his job as the game goes on. He wants to be a durable frontliner who initiates fights and protects his backline, but he can't accomplish either goal against Phantom Assassin. He can't reliably lock her down for his team, and her critical strikes melt his health bar surprisingly fast, even with Bulwark. He’s forced to play reactively against a hero that specializes in dictating the pace of an engagement, leaving Mars feeling more like a speedbump than a fortress.