Instead of Growth Triggers affecting silhouette directly, they add to stats.
Grow Bigger:
For each tier in a talent, roll 1Y
For every Success, add 1 Damage to all Melee rolls
For every Triumph add 1 Armor
Spend Advantage To:
- Boost an Ally
- Impair an Enemy
- Increase your WT
Flavor:
- For each Success, you grow 10% bigger
- For each Triumph, you grow 20% bigger
- For each Advantage you grow 5% bigger
So if you roll 5Y and get: 3 Success, 1 Triumph, 1 Advantage, you grow 155% your current size. If you were 100 feet tall, then you'd grow to 155 feet.
---
GMs could differentiate how they interpret these rolls for size or even stats.
Different abilities, items and talents could provide 'growth rolls' for varying effects.