I was wondering what the toughest AI decks are for people to play against. There's the one deck that always shows up in Paradise Lake and uses 2 Vitalities and a whole bunch of Toxipedes, Jungle Juice, and Natural Orders. I have never been able to make a deck that consistently beats it and it's very frustrating playing against it. I've actually gotten to the point now that when I see it, more often than not, I immediately surrender. I have beaten it before, but with the Toxipedes being so cheap to play and the Vitalities constantly adding life, I've found that the way I usually beat it is by keeping myself alive long enough to deck it.
What do you all think? Are there other decks that give you more trouble or do you agree that this is the toughest one to play against?
I think that every AI deck has its limits and weakness. I play well against toxipedes using a burning world based deck or something that use chronomancer, decay or festerplague (or toxipedes :D) in combo with uncontinue. This is because AI casts toxipedes in every free slot and you can wipe away all of them in a stroke then strike with big minions. It's not easy to win every game but in example I can do it in 70-80% of battles. I quit often when I pick AI decks that have medusa's touch, or those vortex (I don't remember the name exactly) that kills every minion YOU have, in two lines. They're very hard to beat for my gaming style and deck building preferences. Maybe toxipede deck it's your nemesis deck, everyone has their one ;)
For me, there are a lot of AI decks that can potentially make a game unwinnable if I do not expect them and am unprepared with the wrong hand. About half of the power cards can render a few otherwise solid decks completely hopeless while being completely innocuous against others. And, because the AI also "cheats" on deck construction rules, it can exploit combos that generally do not work for human players because the necessary mix of cards in not allowed humans.
The hardest AI deck, in my opinion is Hall of the Underking 19. A combination of medusa touch and vampire touch essentially guarantees that I never have a unit survive a full round until medusa touch expires -- by which time I have almost always lost. Another very nasty deck is Nimbulus 16. The combination of empower and total war fills my enemy ranks with creatures whose strengths I cannot usually match. Luckily, here the factions are air/forest, so at least the minions are not horrible.
Many "tough" AI decks can be easily defeated with the right strategy. Mr. Rouge has given a very elegant solution to the "toxipede deck" -- a solution that also helps with any deck that largely focuses on one creature. On the other hand, I have little trouble with the dark vortex decks that Mr. Rouge mentioned. I can still block the vortex lanes with barriers or with cards like narrow tunnels (although the AI often can remove auras with these decks). I have also found it effective to focus big units on the remaining lanes, while reducing AI strength to 2 or less on the vortex lanes. The AI is too "dumb" to replace a strength 1 bone dragon with a better unit. And I pretty easily defeat most medusa touch decks with my decks containing a lot of units like undead tritons and phantasmas or, of course, pyrohydras. The Champion power card is easily handled with nobbling trickster / hunt combos, or, even better, with bodyswap. Aether is best opposed by pyrohydras, mass delusion, by ancient oaks or by ancient turtles. Etc.
I guess it definitely depends on the deck your playing. I've also found Living Walls to cause major problems, especially with decks that focus on removing minions since walls are tougher to kill. As far as the Medusa's Touch decks go, some of my decks have a tough time with them but my speed decks and decks that focus on pumping up pyrohydras shred them. I even have trouble beating the toxipedes with burning world since they're so cheap and the computer puts two of them out a turn. I'll have to try that other deck you described with uncontinues. Maybe I'll have more luck against the toxipedes with that one. It's definitely my nemesis deck.
Pyrohydras are definitely outstanding against a lot of power cards: not just medusa touch but aether, dragons blood, and vampire touch. But the combo of medusa touch and vampire touch defeats pyrohydras.
An alternative against toxipedes is a deck of cheap but better cards: phantasma, dreamfeeder, undead tritons, doom cloud, whirling djinn, etc. You can then play as fast as the ai -- even replacing cards that time out. And you wear its cards down while occasionally slipping an attack through.