"Fire a short-range, powerful Ki Blast that can be charged up to Stage 3!"
First, the user charges up energy in both of their fists, then fires it out as large energy wave with a limited range. The range can be amplified by charging the attack which can be charged in 3 stages. Piccolo will say "Explosive Demon Wave!" when firing the attack.
Video Game Appearances
Evil Explosion was named and first appeared in Dragon Ball Xenoverse as one of Piccolo's Super Skills. The Future Warrior can also learn this technique by completing Piccolo's Training Qualification Mission after taking Piccolo on as the Warrior's Master.
"Fires a strong, wide-area Ki Blast. Holding down the button will increase the technique's power up to three times."
— Dragon Ball Xenoverse 2 Tutorial description
The attack returns in Dragon Ball Xenoverse 2 as one of Piccolo's Super Skills which he teaches to the Future Warrior as part of Piccolo's Initiation Test. After the 1.09.00 Update, it can be added to Adult Gohan's custom skillset after purchasing it for 5 TP Medals in Partner Customization.
In Xenoverse 2, if the Future Warrior is a Saiyan and uses any Super Saiyan Awoken Skill (SSJ, SSJ2, SSJ3, or SSGSS as well as variants such as Future Super Saiyan, Super Vegeta, and Super Vegeta 2) when they fully charge Evil Explosion to Level 3 then they will use Vanishing to appear next to the opponent then fire in a fashion similar to the Instant Kamehameha (though the teleportation is replaced with simple Rapid Movement). Adult Gohan can also do this when using his Super Saiyan Awoken Skill (Super Saiyan & Super Saiyan 2) with Evil Explosion via his custom skillset.