Drawing 15 cards is pretty sweet
These are the three Id look to first, but have a think
No - newly played characters have a form of summoning sickness, due to their ink still drying, so they cant quest or challenge until your next turn (unless allowed by an expressly listed ability)
Pegasus then activates his face-down "Ultimate Offering", which allows him to Normal Summon more than one monster during his Main Phases and Kaiba's Battle Phases at the cost of 500 Life Points for each extra monster Summoned
Moreover, Secret Packs become available ONLY after you obtain a corresponding SR or UR card of the said archetype
This booster pack provides some support for this archetype, with a lot of reprints: Card list for the archetype Along the cards added, we can note the new Harpie Perfumer that tutors Spell and Traps from its archetype when its Normal or Special Summoned