[syzorst]

The illustration of Crom and Ddraig is their fight in the Rias vs Issei RG. Here's spoilers from the preview.

Spoiler:

Draig punched Crom and got him but Crom punched back. It's stated that Crom's punch did more damage to Ddraig than Ddraig's punch to Crom. Ddraig then uses his fire breath but Crom swats it away with his Dragonified arm. Both Crom and Ddraig uses their fire breath and despite Ddraig using "Boost", Crom's fire breath is still stronger. Ddraig than uses Penetrate on his flames that goes through Crom's flame. Ddraig fire off his red aura similar to Issei's dragon shots. Crom punches them away but he feels damage from it. Ddraig uses a unique technique involving Penetrate into his aura attacks that hits the core of the person even if they block. Ddraig states it's too soon for Issei to learn this technique.

Both Ddraig and Crom are worried they won't be able to finish their fight before the game ends. It's stated that in offensive power alone, Crom is one of the strongest in the tournament (Which is obvious). After Rias is retired, Crom looks at Issei and states that his existence is something of a joke. He has the power of Great Red and Ophis but still only using the power of Ophis. Ddraig replies, "Do you want to fight that "joke" again?". Crom replies yes but he also want to watch over him as he's been influence by the group