Advice against Diana

At some point, she's going to come up in the free week rotation and you're going to see her a lot. Given what I've seen from high level games, I suspect you'll see her alot there too once you start playing ranked. Here's some advice against her.

1) Dodge her Crescent strikes: They come from her right side in an arc so the movement to dodge is different than other casters' skill shots. You want to move at a diagonal. Furthermore, if she's tossing them near  max range, you can probably just step back. if she's tossing them close, a good Diana will aim PAST you. So your best bet is to be already moving back and at an angle or closer at an angle to dodge. The Strike isn't super fast so constant moving is your friend.

2) Monitor your health: If you get hit by a Crescent Strike, back off and heal a bit. I will jump in if I get a second hit on any kind of squishy target so keep that in mind. If that second hit looks like it's going to tag you, start running away BEFORE the lunar strike. She doesn't have much of a close except for it. However, a REALLY good Diana (not me) will use intervening minions to "leapfrog" to you and catch you from MUCH further away then you realize. I've watched people do this and it's awesome.

3) Watch their build: If they've got magic pen boots and Abyssal Scepter, you may want to just build +health items. If they're going with a tankier build with magic resists, you can probably build your own magic resists. Also, the first trip she comes back with an Abyssal Scepter, Needlessly Large Rod or Rabaddon's Deathcap, you need to recalibrate your safety zone.

4) Watch the trees: If Diana's MIA, every hedge row needs to be considered unsafe. I'm not just talking about the bushes either. Crescent Strike plus Lunar Rush can have her leap over anything.

5) Once she snowballs, stop feeding her: This is probably the hardest skill (outside of last hitting) to master for anyone. But it's especially important for Diana. Once she shows that she can gank you solo (which she WILL do), you need to make sure you start fighting under your tower until you can get back in the race. This goes hand in hand with #3 above as the first kill she gets on you probably gives her enough to buy that shiny abyssal scepter that will make the NEXT gank even easier.

6) Harass early then fight under tower: Diana has no range and, until 6, her ability to gank you is very limited. She also has mana issues for most of the game. If you see she's mana low, push hard. She won't build AD and she only has Crescent Strike. Push her under her own tower. When she does hit 6, let her push you back and fight JUST outside your tower. You ideally want to make it so that IF she jumps in, she'll be getting hit by the tower. Watch for pushes from her that get her minions under the tower also, however. This is a good time for her to dive you. To pull off her full combo, she needs around 345 mana (at ~lvl 8). If she's not bought +mana items, that's about 50-60% of her mana. I can't count the number of times I've WANTED to gank and couldn't due to lack of mana. If she's sitting on 20% mana... just push her until she recalls (or, better yet, bait her into jumping in and gank her with a friend).