Does the +7% bonus work against an unknown target in Dragonfire?

No — and it's a trap. The troop triangle's ±7% (Cavalry → Shieldbearers → Archers → Spearmen → Cavalry) is only actionable if you know the defenders' type.

And the enemy type is unknown and random across almost all high-value content:

| Target | Type known? | ±7% usable? |

|---|---|---|

| Tiles below level 10 | yes | yes |

| Tiles level 10+ | no | no |

| Beasts / wild dragons | no | no |

| Hedge Knights | no | no |

| Players (PvP) | if scouted | if scouted |

In practice the ±7% only matters on small tiles (below Lv.10). Against the unknown you may just as easily land at −7%. The trap is choosing your troop type "for the advantage" against a target whose type you don't know → you're flipping a coin.

The right answer: against the unknown, ignore the ±7% and maximize the controllable (research, +20% affinity, auras, Initiative) with a robust comp that doesn't depend on the matchup.