Does The Wanderer's static ability prevent 'destroy' or 'exile' effects from working? In a recent game, I had it out and my opponent tried to cast Doom Blade on a creature. I argued that it shouldn't work, and he said it should have.
Damage is one of the ways a creature can be destroyed, but it's not the only way. The Wanderer only prevents (non-combat) damage, not other "destroy" effects like Doom Blade.
701.7a To destroy a permanent, move it from the battlefield to its owner’s graveyard.
701.7b The only ways a permanent can be destroyed are as a result of an effect that uses the word “destroy” or as a result of the state-based actions that check for lethal damage (see rule 704.5g) or damage from a source with deathtouch (see rule 704.5h). If a permanent is put into its owner’s graveyard for any other reason, it hasn’t been “destroyed.”