At its heart, Affinity is an aggro deck, but since it relies on synergy between its cards to function, it certainly has a combo component to it
Warehouse Krark's Thumb Krark, the Thumbless Mana Clash Mana Crypt Mana Screw Mijae Djinn Mirror March Mirrored Depths Mogg Assassin Molten Birth Molten Sentry Mutalith Vortex Beast Negative Zone Portal Odds // Ends Odds // Ends Okaun, Eye of Chaos Orcish Captain Planar Chaos Plasma Caster Pokey, the Scallywagg (playtest) Puppet's Verdict Rakdos, the Showstopper Ral Zarek Ral, Monsoon Mage Risky Move Scoria Wurm Setzer, Wandering Gambler Skittish Valesk Skyclaw Thrash Sorcerer's Strongbox Squee's Revenge Stitch in Time Tavern Scoundrel Tavern Swindler The Gold Saucer Tide of War Unleash the Flux
It can flip a newly Summoned opposing monster face-down to prevent them from attacking, being used as an Extra Deck material, or activating their effect (assuming it is not a Quick Effect)
On the one hand, it sucks when this becomes collateral damage to a Vandalblast