GoWiPe is an amazing strategy, unattached by any other for taking out the TH in a single fowl swoop, but it does have its rivals. One of those rivals are the Valkyries, and they too can be used at TH8! Without getting into the math, you can assume that replacing your Pekkas with Valkyries retain a similar (if not greater) level of power and hit points, but with the added support of speed! And That's exactly what you need in cleaning up a base for that last Star.
The main problem faced in using GoWiPe, is controlling the army so that the wizards don't outrun the Pekkas/Golems and die to the defenses. They are incredibly important while cleaning up the base, and keeping them alive shouldn't use heal spells. Instead, using Valkyries can keep the tanks ahead of the Wizards, keeping them alive, and out of the defenses' sights! That right there is what helps clean up so dang much! And many people don't consider Valkyries, simply because they're an underrated troop! In all honesty, a full army of Valkyries would probably work best, but no one has the DE to do that every war, ha-ha!
So, when we break this down, we can find out that Valkyries don't lose any power while taking out the core of a base! In fact, their splash damage will obliterate the core of any base in seconds, even without a rage spell! For any lack of power that may be implied, that can certainly make up for it; Not only can they take out the TH, but they can take out the Crossbows, Mortars, and anything else in the core in a single swoop! The only thing left is to gather your troops for clean up duty!
By this point in a GoWiPe Raid, you can expect that what's left of your wizards are now entering the heavy fire fire of everything looking into the core. Your Pekkas may have wandered out to the outside of the base early on, leaving your wizards to barely take the TH, and you're struggling to see how your Pekkas alone can clean this all up.
In a GoWiV attack, on the other hand, the bulk of your firepower is your Valkyries in the first place, and you don't even need to worry about them, because they're decent enough tanks that they're good to go through the whole dang base! While they're going through, you'll realize that Valkyries are not only faster, but excellent at busting through walls without the help of WBs. So, for those bases with hard to get through compartments or with wide open runs, Valkyries can get the job done, and will be able to serve more than that one function of delivering the killing blow! One issue with clean up is solved with Valkyrie's splash damage effect. When a Valkyrie hits multiple buildings at once, it makes it very easy to clear out a compartment, and clean up goes that much faster, compared to the single hit of the Pekka followed by the slow walk to the next building.
The biggest issue facing GoWiPe users is delivering the Pekka to the Core! Even the best of us goof sometimes! Click a tad too far tot eh right, or to the left, and the Pekka goes all the way around to McDonalds for another HappyMeal... However, I've found that not only are Valkyries easy to maneuver and they clean up fast, but they are plentiful! You may only get 2-4 Pekkas in a raid, and that is a massive loss of firepower when one walks off to the side. Not only that, but people generally spam them without checking which direction they're heading off to. That problem is easily avoided though with Valkyries, because of the fact that there are enough of them, that placing one too far to the right doesn't detract nearly as much from the core group-- Oops, too far to the left, better move over to the right! Issue fixed, and the rest are into the middle of the base!
I don't meant o trash talk GoWiPe, because it's an amazing attacking method, and in the right (experienced) hands, it is formidable, but GoWiVa seems *my opinion* to be better overall.
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