Hello guys, I have a question about programming gameplay mechanics ( the game engine used is irrelevant). 

When building a game, let's say an fps, Which approach should you use to get the most efficient results.

1) Build the basic mechanic first e.g A gun that can damage the ai. Then add from there.

Or

2) Build the properties separately to a game worthy state, build the gun, the reload, the ammo, the animations, build the ai enemies, build their animations, their weapons, then link both at the ending.

I have a team, but this is assuming you are a solo dev.

Expecting replies.

Testing the mechanic for working as intended is a huge part of the design phase. What looks good on paper may not work at all in reality. If you cannot test until the last line of code has been written, you are risking a lot of time and effort.

As such, the incremental approach is usually better. I would even start simpler if possible. "AI" is not something simple, it's complicated and needs testing and tuning too like the game mechanic. Use fixed targets, or simple moving targets, or so.

I see, thanks, me and my teammates were having a discussion about this.