Being able to use any amount of spell slots is kinda fun but... it will severely impact balance. Imagine sorcerers with quicken spell and haste. Three fireballs in one round.... o_o
Not being hugely knowledgeable about 5e, I’m not sure how it should work. I agree casting multiple levelled spells as actions seems massively overpowered and would definitely be on board for limiting that. I’m not so fussed about - and in fact like - being able to cast one levelled spell as an action and another as a bonus action (e.g. Thunderwave nearby enemies and Misty Step away) given the spells that use bonus actions don’t tend to be attacking ones. I’m not sure whether even that would be permitted under 5e?
Per 5e rules, you cannot cast one leveled Action spell and one leveled Bonus Action spell in the same turn. Some people agree with what you said--getting rid of this restriction--for various reasons.
Quicken turns an Action-cost spell into a Bonus Action-cost. Thus, a Quickened spell falls under the "no leveled Action + leveled BA spell" rule.
- At the very least, this restriction should be followed for Quickened spells. Otherwise you can get easily the Fireball + Fireball occurrence.
- This could alternatively be balanced by higher sorcery point costs. Something like 2*spell level, so Quickening a Fireball costs 6 points.
Additionally, the "Action" granted by Haste can
only be used for a single attack, the dash/disengage/hide action, or use an object per 5e rules. NOT multiple attacks via Extra Attack. NOT
any spell.
...none of the above restrictions are in BG3.
