What's the optimal strategy for the first Pokémon battle?

Solution 1:

I had a play with a damage calculator I found online and my conclusion is: there are way too many variables to produce a definitive answer: base stats, IVs and Nature all play a part, even at level 5.

If your Pokemon has perfect IVs and beneficial Nature and your opponent has 0 IVs and negative Nature, it looks like you could deal at least an extra 20% damage than if those stats were reversed. I tried a good Snivy against a bad Tepig and got 42% damage from using Tackle, whereas a bad Oshawott against a good Snivy only did 14% damage with Tackle.

In my experience, using any status move is not worthwhile. It always takes the same number of moves before your opponent is KO'd. Example: assume an average damage of 20%, that would normally take 5 Tackles to KO your opponent. If you used Leer first, Tackle would deal ~30% damage (20*1.5). Now it takes Leer + 4 Tackles, so you don't gain anything.

Also note that your opponent uses moves randomly, which you can benefit from: Tackle>Leer>Tackle always does less total damage than Leer>Tackle>Tackle.

My advice: never use more than one status move, and if you do use one always use it as the first move. Then just spam Tackle.

Solution 2:

I've always taken the attack over using status moves. Why?

When you use a status move, you throw away your (small) chance of scoring a critical in that turn if you had just attacked instead. There's no crit chance for using a status move.