Dang, those wyvern kicked my butt....

[RiderUp]

I walked into the swamp feeling all strong, having killed that nasty coccacidium and taken on groups of drowners at once. A couple wyverns walk up and take me down in seconds. Ouch!

[yusupov]

the swamp is easily my least favorite part of this game. no fun to be had there other than ♥♥♥♥♥♥♥ that nature nymph...or do you even get to? i forget...

[MasterZoen]

You can boff her.

I had a lot of fun with the wyverns in the swamp. Just wait till chap 3 when most of them are replaced by Royal Wyverns. They make a wyvern seem like a drowner, LOL. Just use your runes and potions to stack the battle and remember that only short weapons and Silver Fast/Group stances work well on them. It's a good idea to have a high poison resistance going in to a fight with wyverns, as well.

If you've managed to lure one away from the group the Yrden sign can be used to keep them trapped and unable to attack you. Alternatively you can use a short weapon with stun/knockdown modifiers to put it down.

The real trick is taking on the whole group of 6-10 at once. The Samum bomb stuns all enemies within rougly 5 feet of you, letting you lop off one of their heads, just toss another down and repeat up to 10 times. This is the easiest way to handle a group, but the most expensive in my opinion. The Blizzard potion lets you hit and evade them making group stances with the silver sword very deadly. A properly evolved lvl 3 Aard sign(stun, gust, thunder, student, apprentice, specialist) lets you either knock them down or stun them at 1/3 hp or on a crit for a one hit kill.

[Sophie]

That happened to me too, the first time I entered the swamp (the only time I died in my first playthrough). Go level up a bit, also they are quite susceptible to aard. Stun them and get the one hit kill!

[Renegade]

Wut? I didn't see a single Wyvern in chap 2 or 3 outside of the grove.And I'm pretty sure I have explored it entirely.
EDIT: So apparantly there is ''Wyvern island'' which I didn't find :/