You never know what EA are going to throw at us (we've recently realised they are recycling arena tournaments), it's getting a bit more complicated with new plants (who would have guessed zoybean would have lead to record scores).
There are some plants that usually work well in arena, blover, bowling bulb, laser bean, primal peashooter, threepeater and many others but there are others that are virtually useless such as perfume shroom, tallnut*, em peach and stunnion.
Experience tells us which are worth levelling up, the same applies to powermints as some aren't worth using and some are must haves.
I use the infinite practices glitch to work out a decent strategy then i check Tigerol's🐅 weekly post in reddit to see if there's a better strategy for my mighty plant army.
https://www.reddit.com/r/PlantsVSZombies/comments/dr5gq2/arena_pyre_vine_zombot_tuskmaster_10000_bc/?utm_medium=android_app&utm_source=share
*i include tallnut in my list of useless plants as despite having massive health points he is easily outclassed by primal wallnut except for stopping flying zombies.
Thanks to TheRealGamer for providing the zoybean strategy.