Was going to post Iron Treads again, but being a Steel type faster than Cresselia, its not good as a lure. So, we put the other elephant:
Great Tusk @ Booster Energy
Ability: Protosynthesis
Tera Type:
Dark
EVs: 248 HP / 4 Atk / 4 Def / 252 Spe
Jolly Nature
- Bulk Up
-
Knock Off
- Close Combat
-
Zen Headbutt
Usually, Cresselia will see a Speed Booster Energy Tusk and assume Bulk Up (which Tusk will use on the switch) + CC, EQ and Ice Spinner. Cresselia easily walls such a set and even can afford using CM at least once.
However, this Tusk will use Knock Off + Tera Dark instead:
+1 4 Atk Protosynthesis Tera Dark Great Tusk Knock Off (97.5 BP) vs. 252 HP / 4 Def Cresselia: 474-558 (106.7 - 125.6%) -- guaranteed OHKO
Without Tera, it still does a lot:
+1 4 Atk Protosynthesis Great Tusk Knock Off (97.5 BP) vs. 252 HP / 4 Def Cresselia: 316-372 (71.1 - 83.7%) -- guaranteed 2HKO
Of course, Cresselia might predict the Knock Off, transforming the calc into either this:
+1 4 Atk Protosynthesis Tera Dark Great Tusk Knock Off (97.5 BP) vs. 252 HP / 4 Def Tera Poison Cresselia: 237-279 (53.3 - 62.8%) -- guaranteed 2HKO
Or this:
+1 4 Atk Protosynthesis Great Tusk Knock Off (97.5 BP) vs. 252 HP / 4 Def Tera Poison Cresselia: 158-186 (35.5 - 41.8%) -- guaranteed 3HKO
But if Cresselia does that, it won,t be able to kill Tusk in 2 hits anyway:
0 SpA Tera Poison Cresselia Moonblast vs. 252 HP / 0 SpD Great Tusk: 180-212 (41.4 - 48.8%) -- guaranteed 3HKO
Meanwhile, after seeing Tera Poison, Tusk will reveal the second secret weapon, Zen Headbutt:
+1 4 Atk Protosynthesis Great Tusk Zen Headbutt vs. 252 HP / 4 Def Tera Poison Cresselia: 260-308 (58.5 - 69.3%) -- guaranteed 2HKO
35,5 + 58,5 = 94 is the minimum damage Tusk will do without Tera with Knock Off + Zen Headbutt. If Tusk goes Tera, it will always KO in 2 hits (unless miss) while always (unless crit) avoiding the 2HKO from Moonblast. This Great Tusk succesfully lures and eliminates one of the biggest standard Great Tusk counters. Tera helps, but its not even needed to almost always defeat Cresselia.