You can't move and shoot in an opposite direction, which also factors into the game's difficulty. With friends, you can use one person as bait, while the others fire away from a distance - something you can't do solo. I'm not a big fan of the idea, but at the same time, it's an interesting design decision. Enemies come at you from all sides, forcing you to prioritize enemies. However, the underlying gameplay doesn't support this mechanic. Enemies swarm you, so there's no way to effectively check-off which target to go for first. I couldn't begin to count the number of cheap hits I had to absorb because I had to shop, then shoot.
As you go through levels, you'll eventually stumble across helpful potions. Green potions, which recover your health, are priority one. There aren't many in the game, so it's also important that you ration when you use them. Even more important are blue potions, which allow you to use your character's special attack. These damage everyone on the screen and can bail you out of a tight spot. Finally there are Red potions, which heal your party. These are just as vital as green potions, though when playing with others, you can also revive downed members.
Knowing when to use potions is one of the few major, meaningful choices you'll need to make in the game. The Hearts of Men is a fun throwback, but it's the lack of these sorts of decisions that hold it back. Getting to the end of the level isn't enough; other factors need to conspire to keep me from getting there, while at the same time, motivating me to want to press on.
Like most board games, there's a direct relation between the amount of fun you'll have and the people you're playing with. If you like the idea of getting a group of friends together for a simple game night, The Hearts of Men should be on your play list. Otherwise, The Hearts of Men is a good title, but one you'll want to try before buying.