F2P friendly

Marowak EX was initially accompanied by Dugtrio because of its low retreat cost and damage prevention with Dig. However, since Promo Mankey has been introduced, Marowak EX can be paired with hard-hitter that allows you to inflict heavy damage from second turn, no matter what Pokémon you open the battle with. Quick offensive can be successful against decks that require little more time to prepare for heavy attacks. 

Depends on your opening hand, you can start the fight with either:

Strategy is to use Weezing to stall and poison until Alakazam is ready, then use Koga for a "free" retreat. Energy is Dark/Psychic, each Pokemon only needs a single coloured pip to function. Weezing is mostly there to act as a meatshield and poison, but I have found the fail rate of "you only get Dark energy" low enough to be worth the extra attacker. 

Like every other deck, a game where you can reasonably curve out Alakazam will be a good game. 

----

Mythical Island Update

This deck requires a bit of skill to use, but it’s proven powerful against many EX decks. The main strategy centers on building up both Melmetal and Butterfree to maximize their abilities. Melmetal’s "Hard Coat" ability automatically reduces incoming damage by 20, while Butterfree’s "Healing Powder" restores 20 HP each turn to both your active and benched Pokémon. Together, they effectively reduce 40 damage per turn.

It's fun!

Try to get both Butterfrees rolling for maximum heal, while Exeggutor tanks. Swap so you can heal other Exeggutor in bank. And only get heads.

Deck Source

Low barrier to entry, easy to play, non-ex deck that consistently wipes many meta Genetic Apex decks (including Pikachu ex and Mewtwo ex). 

Remember to turn dark energy generation off in the deck builder  -- this deck does not use it.

The main strategy is to set up Dragonair on the bench as soon as possible. Keep Weezing active while setting up. 

This deck guarantees Mankey in your opening hand, with Poké Ball available to quickly pull a second Mankey if needed. The Promo Mankey is essential, as its move causes 10 self-damage, allowing for an easy evolution setup that hits for 100 damage per turn with Primape's "Fight Back" attack. While less effective, the Apex Mankey can be substituted until two Promo Mankeys are able to be included. Kabutops serves as an effective staller to build up additional Primape as it is a strong hitter with high self-healing capabilities.