Tackling the 'Merlin Trials' in 'Hogwarts Legacy' really rewards planning, and the spells you pick change the whole rhythm of a run. For raw reliability I lean hard on your shield and stun tools: the Shield Spell (Protego) and the Stunning Spell (Stupefy) are lifesavers. Protego blocks heavy hits and lets you create breathing room to heal or reposition, and a well-timed Stupefy staggers
enemies so you can break combos or finish with an AoE. I prioritize upgrading these early because the survivability payoff is huge.
Beyond that
Foundation, you want crowd control and area damage. Spells that pull, lift, or lock enemies in place — think summoning or levitation effects — let you isolate dangerous foes (sorcerers or heavy hitters) while you clear trash mobs with explosive or AOE spells. Pairing a crowd-control charm with a wide burst spell lets you chain-cleave rooms instead of getting overwhelmed. Also, keep a reliable single-target nuke for bosses who cheese through shields; upgrades that reduce cooldowns or extend effects make the combos feel buttery.
Finally, remember utility: mobility and item-support spells (or their equivalents) that let you kite, reposition, or interrupt spells can turn a near-fail into a perfect run. Potions and gear that boost spell cooldown, damage, or critical chance will often matter more than swapping to a flashy new offensive spell. In short: Protego, Stupefy, solid crowd-control (levitation/summoning type), an AoE nuke, and a focused single-target spell — kit those up, tweak based on the trial room, and you'll see steady improvement. Happy hunting — these trials are brutally fun once you find your groove.