I decided to restart HeartGold...
1) For that playthrough I plan to use only Gen II Pokémon.
2) This in-game team is only for the first part of the game (the 8 Johto Badges+Elite 4). I'll add the team for the second part (the 8 Kanto Badges+Red) later.
3) Also Natures, EVs and held items will not be considered, only the Abilities and Moves.
The starter and the best Fire-type available since there aren't any decent Gen II Fire-types, besides Houndoom which is post game, I can't trade Magmar and Arcanine can't be used due to the Gen II only rule.
Note: Focus Blast's accuracy is too low to be useful ingame.
Ability: Serene Grace
One of my favourite Gen II Pokémon and it's available early, thanks to a Kinomo Girl.
Since the Shiny Stone isn't available before facing the Elite 4 and therefore I can't get Togekiss, Togetic will be my Flyer.
Electric-types are useful mainly against Water-types and Falkner is dead meat because Mareep is available before the Gym Match.
Ability: Water Absorb
Surf (just a filler)
Emeraldfan suggested a physical based Water or physical based Grass type and the best choice was Quagsire, though it shares a Grass-type weakness with Mamoswine, Typhlosion and to a certain extent Ampharos can cover the Grass-type weakness very well.
And something says I'll like Quagsire's derpish face...
Another gift Pokémon and my favourite Eeveelution.
Well... its moveset is crappy since I have no access to most useful moves (either TMs and Move Tutors).
Though it's available a little late (after the 7th Gym and the Team Rocket events), I know a powerhouse when I see one and Dragon-types won't stand a chance against Mamoswine.
The double Ice STAB depends of how faster (Ice Shard) or slower (Ice Fang) my opponents are than Mamoswine.