Pikachu packs a punch right out of the gate and has a low retreat cost
I will use it in Constructed, but only with mono-black Zombies
Once we have a board in play, we can protect our source of recursion
It will grow as my army grows, it will make my creatures harder - or impossible - to block, and it will also help me have a big creature to attack with so I can get those Training triggers
As long as your opponent isnt playing with an insanely powerful or convoluted deck that can hit hard on the first turn, your Riolu should be able to hold on until you can get Lucario into play it has a reasonable 70 HP, which can withstand many early game attacks, along with a Punch (costing 1 Fighting Energy to use) that deals 10 HP of damage
the card art -- front and back -- is also the same