Suggestion: an "odd" laboratory to upgrade miscellaneous aspects
This idea is an "odd" laboratory which upgrades miscellaneous aspects of some troops and spells.
For example:
Dragon - his AI is upgradable. A commonly suggested idea on the forum is to "improve dragon AI", but this suggestion is to upgrade his AI with elixir, rather than simply improving the AI (which instantly applies to all players). Higher AI levels make dragons smarter.
Wallbreaker - same as dragon, to improve AI.
Witch and Lava Hound - improve the stats of their subtroops (skeletons and lava pups). Improved skeletons also apply to the same player's skeleton traps.
P.E.K.K.A - unlocked if player's P.E.K.K.A has been upgraded to level 4. Because level 4 and 5 P.E.K.K.As have two swords, the odd laboratory upgrades the chance to strike with both sword (doing double damage) and decreases the damage multiplier taken from hidden teslas (for example to 1.5 at maximum level)