Bria's final ability disincentivizes combat tricks : making your creatures unblockable is only useful before your opponent has an opportunity to declare blockers, so you shouldn't feel bad about using lots of sorcery-speed effects during your precombat main phase
Legendary Creature - Wizard Vampire Ria Ivor, Bane of Bladehold Battle cry (Whenever this creature attacks, each other attacking creature gets +1/+0 until end of turn.) At the beginning of combat on your turn, the next time target creature would deal combat damage to one or more players this combat, prevent that damage
Adaptive Snapjaw Agent's Toolkit Ajani's Welcome Akroma, Angel of Wrath Avatar Angel's Tomb Angelic Chorus Answered Prayers Aura Shards Authority of the Consuls Battering Krasis Beck // Call Beck // Call Blood Seeker Bloodhill Bastion Boxing Ring Case of the Uneaten Feast Cathars' Crusade Clinging Anemones Cloudfin Raptor Cool Fluffy Loxodon Crocanura Decoction Module Dinosaur Egg Dredging Claw Durable Handicraft Electropotence Elusive Krasis Ephara's Enlightenment Experiment One Familiar Beeble Mascot Fathom Mage First Day of Class Geek Lotus Warrior Gluttonous Slug Gyre Sage Huatli, Radiant Champion Ichorplate Golem Illusory Gains Immersturm Impact Tremors Intruder Alarm Kiora, Master of the Depths Leyline of Vitality Llanowar Reborn Lonis, Genetics Expert Lukka, Wayward Bonder Mace of the Valiant Malfegor Avatar Mana Echoes Mirror of Life Trapping Murderous Redcap Avatar Nurturing Presence Pandemonium Path of Discovery Plane-Merge Elf (playtest) Prison Term Prized Amalgam Propagator Drone Renegade Krasis Sai of the Shinobi Scurry Oak Season of Growth Shambleshark Sharp-Eyed Rookie Shielded by Faith Sigil Captain Simic Fluxmage Simic Manipulator Stonehewer Giant Avatar Stormrider Rig Suture Priest Trespasser's Curse
In other words, if a creature has flying, it can only be blocked by another creature with flying
