Ferrothorn:
Grass/Steel type
Iron Barbs/
Filter/
Forewarn (HA)
Ability changes:
Iron Barbs: Now deals damage even if the contact move is blocked by Protect, Spiky Shield, or King's Shield. Detect still prevents Iron Barbs from working, as the user evades attacks rather than blocking them outright.
Forewarn: Now lasts 4 turns, displaying each move in the foe's set in descending order of base power at a rate of one move per turn. Additionally, moves revealed by Forewarn are guaranteed to miss against this Pokémon on the turn it reveals them.
Base stats:
105/
124/
161/54/
141/
15 BST:
600
Moveset additions: +Spiky Shield, +Powder, +Magic Coat, +Mimic, +Headbutt, +
Catapult (with all due respect to
zerobreaker000, your move is amazing and I'm borrowing it for mine too)
New moves and move changes:
Catapult:
Type: Rock
Category: Physical
Power: 55
Accuracy: 85%
Target: Any
PP: 8
In-game description: The user lobs nearby pebbles at the opposing side. If Stealth Rock is active on the user's side of the field, this move's power doubles and Stealth Rock is removed.
Effect: Doubles in base power if Stealth Rock is on the user's side. Removes stealth rock from the user's side if the move hits.
Bomb move.
Also while we're at it, an item modification:
Rocky Helmet: Now deals damage even if the contact move is blocked by Protect, Spiky Shield, or King's Shield. Detect still prevents a Rocky Helmet from working, as the user evades attacks rather than blocking them outright.
Reasoning:
So how about that Forewarn buff though?
Ferrothorn can now remove Stealth Rock via that nice new move, Catapult. It has increased bulk as well to help deal with the increased power of most of the threats running around this tier. Additionally, it is now even slower, meaning it gets maximum power on Gyro Ball just a little bit easier. Spiky Shield just makes sense and makes it an even better physical wall, letting it stall for leftovers recovery while also dealing chip damage to foes with contact moves. Magic Coat lets it avoid being Burned and also stops hazards before they can be put up in the first place. Powder takes care of that Fire-type weakness. Iron Barbs is still Iron Barbs, but now also synergizes beautifully with Spiky Shield. Filter mitigates its Fighting weakness and drastically reduces its Fire weakness, from 4x to 2.25x. Forewarn serves as an amazing scouting tool, as well as possible protection against a foe's most powerful attacks right when they try to use them. It also gets Ferrothorn a lot of free switch-ins.
Mimic is just there because everything that learns standard TMs learns Mimic thanks to the Mimic Girl in Kanto. Similarly, Headbutt is there due to the tutor in Johto who teaches it so you can hit trees to get Pokémon to fall out.