This all happens during the declare attackers step, meaning phase-savvy players will be able to sneak a Colossus Hammer onto something with some evasion and surprise their opponents with a bonus 10 damage
That said, there are some strategies that can synergize with Sarkhans Ultimate
1 Miriam (Illustration Rare) Who knows what tomorrow may bring, but as of this writing, the most valuable card in the Pokemon TCG's Scarlet & Violet expansion is Miriam (Illustration Rare)

Metagame Breakdown 146 ABC (143 ABC, 1 Artifact ABC, 1 Brilliant ABC, 1 Symphonic Warrior ABC) 118 Metalfoes (117 Metalfoes, 1 Speedroid Metalfoes) 84 D/D 69 Blue-Eyes (67 Blue-Eyes, 2 Ritual Blue-Eyes) 23 HERO (22 HERO, 1 Synchro HERO) 21 Darklord (19 Darklord, 1 Speedroid Darklord, 1 Speedroid Burning Abyss Darklord) 15 DARK Synchro 14 Burning Abyss (11 Speedroid Phantom Knights Burning Abyss, 1 Ritual Burning Abyss, 1 Speedroid Burning Abyss, 1 Speedroid Nekroz Burning Abyss) 10 Frog (7 Speedroid Frog, 2 Frog, 1 Frog Paleozoic) 9 Monarch (3 Brilliant Monarch, 3 Domain Monarch, 2 Speedroid Artifact Monarch, 1 Artifact Brilliant Monarch) 6 Yang Zing (4 Speedroid Yang Zing, 2 Metalfoes Yang Zing) 5 Kozmo (4 Kozmo, 1 Speedroid Kozmo) 3 Infernoid 3 Nekroz (2 Shaddoll Nekroz, 1 Nekroz) 3 Qliphort 3 Yosenju 2 Cyber Angel 2 Junk Doppel 2 Lightsworn (1 Lightsworn, 1 Shiranui Lightsworn) 1 Barrier Statue 1 Dark Magician 1 Denglong FTK 1 Galaxy 1 Lightsworn Shiranui 1 Ritual Beast 1 Speedroid Phantom Knights 1 Tellarknight ABC The early ABC builds were running Galaxy Soldier and Transmodify

In commemoration, Konami made their 10,000th card an effect card called the Ten Thousand Dragon
Maze's End Gates are better in Commander with the printing of Baldur's Gate and Gond Gate, but I still think it unlikely that this works outside of Nine-Fingers Keene decks, and honestly, even in those decks