Cannot be Special Summoned. This card can attack twice during each Battle Phase. During your Standby Phase, if this card was destroyed since your last Standby Phase: You can Special Summon 2 "Double Dude Tokens" (Warrior-Type/DARK/Level 4/ATK 1000/DEF 1000). This card must be in your Graveyard to activate and to resolve this effect.
Letting Double Dude be able to attack directly can mean an easy 2000 damage, while ignoring your opponent's monster. This can be a good way to deal damage if you can protect yourself from getting OTKed on your opponent's next turn. After Double Dude gets destroyed, 2 tokens will be summoned. They won't be able to attack twice, but you can use cards like Cross Attack, or simply just tribute summon, Double Magical Arm Bind, or Enemy Controller tribute take for some more damage.
You can use the 2 tokens to special summon Atmosphere, or normal summon/set another monster so you can special summon Plasma. These 2 monsters are both special summon, and can take control of your opponent's monster to gain some attack. If you have cards like Double Magical Arm Bind, or Enemy Controller, then you can take control of your opponent's monster and use them as the cost of tributes instead. If you use Atmosphere, you can take 1 of your opponent's monster, then normal summon to potentially end the game early.
Activates from your Graveyard
Cannot Special Summon / Special Summons Tokens
this guy's not in the D-Hero meta, but he's won me so many games, either through the double attack + dark city, or the two tokens during the standby phase. Great card.