I've been running two Pokemon as pure annoyances and to Mega Lucario, these two both make it hard for Mega Lucario to get past them. They don't have huge uses in OU but, still. Here they are:
Mismagius @ Choice Scarf
Ability: Levitate
EVs: 252 HP / 252 Def / 4 SpA
Bold Nature
- Will-O-Wisp
- Trick
- Shadow Ball
- Memento
Mismagius is actually a decent counter! It doesn't need any Speed Investment to outspeed Mega Lucario (it essentially has ~118 Speed). Trick is used for everything else. Will-O-Wisp cripples Mega Lucario beyond return! Memento is to pull off Will-O-Wisp -> Switch Out -> Switch In -> Memento, to leave Lucario Burned with -2/-2. It also helps against the opponent if you know they're running Special Lucario, Will-O-Wisp will just slowly wether it. Shadow Ball 2HKOes after Burn, here are some calcs:
252 Atk Adaptability Mega Lucario Bullet Punch vs. 252 HP / 252+ Def Mismagius: 94-112 (29 - 34.5%) -- 5.2% chance to 3HKO
252 Atk Mega Lucario Crunch vs. 252 HP / 252+ Def Mismagius: 186-220 (57.4 - 67.9%) -- guaranteed 2HKO
252 Atk Adaptability burned Mega Lucario Bullet Punch vs. 252 HP / 252+ Def Mismagius: 47-56 (14.5 - 17.2%) -- possible 6HKO
252 Atk burned Mega Lucario Crunch vs. 252 HP / 252+ Def Mismagius: 93-110 (28.7 - 33.9%) -- 0.9% chance to 3HKO
4 SpA Mismagius Shadow Ball vs. 0 HP / 0 SpD Mega Lucario: 121-144 (43 - 51.2%) -- 5.9% chance to 2HKO
4 SpA Mismagius Shadow Ball vs. 0 HP / 0 SpD Mega Lucario: 121-144 (43 - 51.2%) -- 98% chance to 2HKO after burn damage
It is a decent Counter, and a really good check. It just isn't that good overall in OU.
Pelipper @ Leftovers
Ability: Rain Dish
EVs: 252 Def / 252 HP / 4 SAtk
Bold Nature
- Hurricane
- Scald
- Roost
- U-turn
Ok, here it is. One of the best counters. Seriously, before I go in-depth, look at these calcs:
252 Atk Adaptability Mega Lucario Close Combat vs. 252 HP / 252+ Def Pelipper: 102-121 (31.4 - 37.3%) -- guaranteed 4HKO after Leftovers recovery
252 Atk Adaptability Mega Lucario Bullet Punch vs. 252 HP / 252+ Def Pelipper: 34-41 (10.4 - 12.6%) -- possibly the worst move ever
252 Atk Mega Lucario Crunch vs. 252 HP / 252+ Def Pelipper: 68-81 (20.9 - 25%) -- possible 5HKO after Leftovers recovery
its only hope, Thunder Punch:
252 Atk Mega Lucario Thunder Punch vs. 252 HP / 252+ Def Pelipper: 256-304 (79 - 93.8%) -- guaranteed 2HKO after Leftovers recovery
doesn't even OHKO. Then lets do this at +2:
+2 252 Atk Adaptability Mega Lucario Bullet Punch vs. 252 HP / 252+ Def Pelipper: 68-81 (20.9 - 25%) -- possible 5HKO after Leftovers recovery
+2 252 Atk Mega Lucario Crunch vs. 252 HP / 252+ Def Pelipper: 136-161 (41.9 - 49.6%) -- guaranteed 3HKO after Leftovers recovery
+2 252 Atk Adaptability Mega Lucario Close Combat vs. 252 HP / 252+ Def Pelipper: 204-241 (62.9 - 74.3%) -- guaranteed 2HKO after Leftovers recovery
then, +4:
+4 252 Atk Adaptability Mega Lucario Bullet Punch vs. 252 HP / 252+ Def Pelipper: 102-121 (31.4 - 37.3%) -- guaranteed 4HKO after Leftovers recovery
+4 252 Atk Adaptability Mega Lucario Close Combat vs. 252 HP / 252+ Def Pelipper: 306-360 (94.4 - 111.1%) -- 68.8% chance to OHKO
+4 252 Atk Mega Lucario Crunch vs. 252 HP / 252+ Def Pelipper: 204-241 (62.9 - 74.3%) -- guaranteed 2HKO after Leftovers recovery
finally, +6:
+6 252 Atk Adaptability Mega Lucario Bullet Punch vs. 252 HP / 252+ Def Pelipper: 136-161 (41.9 - 49.6%) -- guaranteed 3HKO after Leftovers recovery
+6 252 Atk Mega Lucario Crunch vs. 252 HP / 252+ Def Pelipper: 272-320 (83.9 - 98.7%) -- guaranteed 2HKO after Leftovers recovery
+6 252 Atk Adaptability Mega Lucario Close Combat vs. 252 HP / 252+ Def Pelipper: 408-480 (125.9 - 148.1%) -- guaranteed OHKO
It needs +6 to even guarantee a OHKO. In the meantime, it gets burned:
+6 252+ Atk Adaptability burned Mega Lucario Close Combat vs. 252 HP / 252+ Def Pelipper: 223-263 (68.8 - 81.1%) -- guaranteed 2HKO after Leftovers recovery
meanwhile:
4 SpA Pelipper Hurricane vs. 0 HP / 0 SpD Mega Lucario: 139-165 (49.4 - 58.7%) -- guaranteed 2HKO after burn damage
4 SpA Pelipper Scald vs. 0 HP / 0 SpD Mega Lucario: 102-121 (36.2 - 43%) -- guaranteed 3HKO after burn damage
This will add up to 109.6 - 125.7, combined, with Burn. This will kill it off. I mean, I was that guy who used Pelipper in OU so... Most people don't even remember it haha, but it is one of my bros. Anyways, I'll explain the Moves/EVs now! Scald is for that burn, plus it hits pretty hard with STAB. Hurricane is a secondary STAB move, that hits really hard! U-Turn keeps up momentum, while Roost keeps it alive and healthy! The EVs are odd, as you'd think you'd want 248/252 so that you hit an odd number for SR, but on Pelipper it won't matter, as Roost keeps it healthy really. It also turns Mega Lucario's 252 Close Combat into a 4HKO, which is a 3HKO with 248. It might seem small, but if you switch in, that's one, take another one, that's two and you hope for the burn, then three, it kills you. This is a tiny thing, but it means leaps and bounds. I'm building a team with this fearsome bird right now actually! The RMT should be up soon, but that's off the point. Anyways, Pelipper is one of those niche mons that is a great counter to a top OU Threat!