I chose to play as a pure fighter in a campaign. Went with warforged, opted play as a samurai, and started out as lvl 4.
I enjoy the campaign, and I feel like I'm fairly helpful in our random basic encounters, dealing a fair amount of damage. However, I feel completely ineffective when facing the more imposing enemies.
Our first end of dungeon boss was immune to non-magical attacks and his bodyguard resisted damge from non-silvered weapons. We slogged through the encounter, with my character only being able to do half damage the entire time. Then we had our next big confrontation at lvl 6, this time I've been able to silver edge my weapon but we are put up against a single vampire (five people in our party: Fighter/Rogue, Fighter, Barbarian, Sorcerer, Cleric). Again, I'm stuck only doing half damage, watching as the vampire recovers health every round and our party gradually succumbs to its charm ability. Eventually all of us are unable to fight and our session ended on a cliffhanger as to whether or not we just got party wiped.
If my character is going to be constantly running into creatures resistant to his attacks, what are some options he can take to be effective in combat without access to a magical weapon?