Imanalt, Seviper is holding a smoke ball. This has nothing to do with priority.
Smoke Ball: The Pokemon negates all of its own accuracy drops, all of its opponent's evasion boosts, and the effects of an opponent's Double Team. Actions used evasively always fail against the Pokemon. If the opponent uses Dig, Bounce, or similar moves, the carrier of Smoke Ball always strikes just before the opponent can take evasive action, even if it would normally be slower.
The combo goes before Lucario even burrows, let alone emerges.
Hi jump kick, substitute 15, reversal
If protect a1, change actions to substitute 25, reversal, hi jump kick+hi jump kick
If protect a1 and a3, change actions to substitute 25, hi jump kick, Chill
Fighting: Fighting STAB; ignore weight restrictions of throwing/grappling moves. Superior reaction time in close quarters. Steel:Steel STAB; immune to Sandstorm, highly insusceptible to toxic attacks, but can be corroded specifically by Acid and Acid Spray, can be magnetized. Superior senses in high-metal environments like construction sites or factories.
Inner Focus: (Innate) When an opponent attempts to flinch this Pokemon, it stands firm and continues its attack. If it has another ability that would be activated by flinching, that ability activates. Steadfast: (Innate) If this Pokemon is flinched, it becomes aware of the speed difference and increases speed by one (1) stage to make up the difference. This speed boost is maintained at the end of each round. Justified: (Innate) This Pokemon's body reacts to dark energy, invigorating its passions. When hit by a Dark-type move, the Pokemon's attack will increase one (1) stage. A boost gained this way by another Pokemon's attack will be maintained at the end of each round. Self-targeted attacks do not maintain boosts.
Hi Jump Kick(*)
Water: Water STAB; Can breathe and have excellent mobility when underwater, are less capable on land unless they are entirely amphibious. Ground:Ground STAB; Immune to all electrical attacks, can Dig through almost any substance, Evasive Digging reduced from 6 per action Energy Cost to 5 per action, superior senses in darkened cave surroundings.
Sticky Hold: (Innate) This Pokemon’s body is covered in a sticky substance that prevents item theft or swapping. Storm Drain: (Innate) This Pokemon lures all water attacks to itself, altering their course away from partner Pokemon. It absorbs the water and increases its Special Attack by one (1) stage. A boost gained this way by an opponent's attack will be maintained at the end of each round. Self-targeted attacks do not maintain boosts. Sand Force (DW): (Innate) This Pokemon thrives in Sandstorm conditions, using the power of the swirling sand to augment its Rock, Ground, and Steel-typed attacks. Each of this Pokemon's Rock, Ground, and Steel-typed attacks will have the Base Attack Power increased by two (2). Pokemon with this ability are immune to Sandstorm damage.
Hidden Power Grass Power 7(*)
Mamoswine TUSKS (m)
Nature: Mild (+satk, -def)
Ice: Ice STAB; immune to freezing and Sheer Cold, no vision loss or damage in Hail or snowstorm conditions, perfectly accurate and 30% Protect breaking Blizzard in Hail. Superior senses and mobility in frozen caves and other frigid arenas. Ground: Ground STAB; Immune to all electrical attacks, can Dig through almost any substance, Evasive Digging reduced from 6 per action Energy Cost to 5 per action, superior senses in darkened cave surroundings.
Oblivious: (Innate) This Pokemon is incapable of being affected by Attract, Cute Charm, or Captivate. Snow Cloak: (Innate) This Pokemon is used to snowy blizzard conditions and gains a 20% evasion boost during Hail. Pokemon with this ability are immune to Hail damage. Thick Fat (DW) (Innate) This Pokemon has a great deal of extra fat or muscle that increases its resistance to extreme heat or extreme cold, reducing the type effectiveness of Fire- and Ice-typed attacks to the next level of resistance (2x weak becomes neutral, neutral becomes resistance, etc.)