Others have basically said it. It would be stuff like Gazer FL combos with poison (e.g. Scorpiogeist) and double TT or GT looping. Of course, big counters to that would be camouflage (or possibly even poison immunity) so we’d see some of that.
Scorpiogeist being 80% speed and toxic entrance not restricted from the start of the battle would be very hard to ignore. It would probably be very common. However, if there was any place for it I bet some people would go for Bastia with her instant win on the first turn (she’d also disable Gazer / toxic entrance).
We’d probably also have some cannibalise single stun revenge giving turn to stun counters stuff.
Basically, really fast front lines would be commonplace and there’s a few horrible things that were removed which enabled full control (e.g. Bastia original release, GT loops, double/triple TT possibly even the shocking entrance being 160s).
Final thing to note is one of the early nerfs to give turn that gave it a use limit of 5. If that never happened then someone who’s losing could infinitely give turn to their own monster to wait until the opponent disconnects.
Yeah that wasn’t anywhere near as bad. You need to remove/kill enemies with Cynthia on the battlefield then have Nefariodon enter afterwards. Not anywhere near as easy to do and not as fast as the 80-90% speed TT looping.