Impactful ability or abilities: Simply boosting power and toughness is almost never enough to make an equipment playable outside of certain Voltron builds (strategies that load up one creature, often a commander, to be as big as possible through multiple sources)
Twenty +1/+1 counters isnt hard
Krovikan Horror and Ashen Ghoul make for an engine that can overwhelm an opponent turn after turn
Giada, Font of Hope A Legendary Creature from Streets of New Capenna, Giada, Font of Hope might be the perfect commander for an angel tribal EDH deck
There are only 10 Companion cards in total, each one created for Ikoria
Rough and Tumble Creature (24) Asmodeus the Archfiend Black Dragon x2 Cleaving Reaper Cragplate Baloth Dauntless Survivor x4 Dragonsguard Elite Karfell Kennel-Master x2 Murasa Brute x3 Oran-Rief Ooze Scurrid Colony x3 Specter of the Fens x2 Vampire Spawn x3 Instant (6) Might of Murasa x4 Oblivion's Hunger x2 Sorcery (3) Rabid Bite x3 Land (27) Evolving Wilds x4 Forest x12 Swamp x11 There isnt a ton of synergy between the black and green cards in Rough and Tumble