TERA REVERSAL
Premise: ALL your Pokemon start the game Terrastalised into a type of your choosing. ALL Pokemon can cancel their Terastallization and return to their original typing at any time. You can cancel up to 6 of your Terrastallizations (your entire party). You cannot Tera again after a cancellation.
Quick clarification: at the moment, my idea is you start Tera'd so you keep both your original STAB and gain the Tera boost. For example, a Tera Ice Great Tusk still keeps its Ground and Fighting STAB as well as gain a STAB on Ice Spinner. If you cancel the Tera, you lose the Ice STAB. If you are Tera Ground Great Tusk, your Ground moves gain the Tera damage boost on top of your STAB, but the downside is you can't flip your defensive typing as much if you do this.
Potential Bans and Threats: probably OU-esque banlist. I think Immune abilities naturally get better. The real question is if people woukd enjoy the 50/50s or not. I think this OM highly rewards predictions and will have volatile swing turns.
Questions:
1. What do you think of the way the Tera damage boost work? Would it be better if you lose your natural STABs?
2. Do you think this om would be too punishing for bad players?
3. What are some broken mons you can think of?