The secondary attack Max Bullet is more damaging, dealing 160 damage to the opponent and a further 60 damage to any of his/her benched Pokmon
The smart use of both makes or breaks a deck

Ezuri +1/+1 Counters Ezuri, Claw of Progress | Illustration by Livia Prima Commander (1) Planeswalkers (2) Nissa, Voice of Zendikar Jiang Yanggu, Wildcrafter Creatures (30) Elvish Mystic Fyndhorn Elves Llanowar Elves Blighted Agent Cankerbloom Coiling Oracle Devoted Druid Gyre Sage Incubation Druid Invisible Stalker Quirion Beastcaller Sage of Hours Thrummingbird Champion of Lambholt Cold-Eyed Selkie Edric, Spymaster of Trest Evolution Sage Kami of Whispered Hopes Managorger Hydra Marwyn, the Nurturer Rishkar, Peema Renegade Tuskguard Captain Vorel of the Hull Clade Fathom Mage Forgotten Ancient Lulu, Stern Guardian Siren Stormtamer Master Biomancer Cultivator of Blades Mycoloth Instants (12) Bioshift Silkguard Slip Out the Back Tamiyo's Safekeeping Counterspell Experimental Augury Growth Spiral Negate Reality Shift Serum Snare Inspiring Call Steady Progress Sorceries (7) Thirsting Roots Contentious Plan Nature's Lore Rampant Growth Unnatural Restoration Cultivate Tezzeret's Gambit Enchantments (9) Hardened Scales Kenrith's Transformation Awakening Zone Bred for the Hunt Garruk's Uprising Jugan Defends the Temple Levitation Primal Empathy Wizard Class Artifacts (2) Contagion Clasp Swiftfoot Boots Lands (37) Ash Barrens Brokers Hideout Evolving Wilds Forest x14 Hinterland Harbor Island x9 Karn's Bastion Lumbering Falls Mosswort Bridge Oran-Rief, the Vastwood Simic Growth Chamber Tangled Islet Tanglepool Bridge Temple of Mystery Thornwood Falls Yavimaya Coast Ezuri, Claw of Progress is a deck that takes a little time to get going, but quickly snowballs out of control

Even later games like my favorite, Nightmare Troubadour, would have issues like this because theres a lot of logic required for certain effects to work properly
This card is a favorite in Lightsworn decks, and it would not be uncommon to have three of these in use at a time
While it doesnt entirely lack removal, many of its best effects are locked behind an artifacts ETB, meaning your opponents have ample time to respond if you waste your entire turn casting Spine of Ish Sah