Delirium challenges you as a player to think critically not only as a deckbuilder, but as a player as well
In the G-on regulation, examples include: Mimikyu (ex) Milotic (Tera) Ogerpon Cornerstone Mask (with Ability) Since Tera = a type of ex Pokmon, if you look only at the Ability while ignoring HP, etc., Mimikyu is a superior version of Milotic
Games Can End In Just A Few Turns Yu-Gi-Oh
Many of them have too few of a HP, as spirits do not have flesh which renders moves like Pain Split an absolute but gimmicky necessity that serves more to damage the opponent than to heal the Pokmon, and since revives kill zombies, they generally do not have standard healing moves, and their defensive variants do not have the power to abuse drain moves, if they even have access to Drain moves.
With sideboard plans that ranged from splashing for counterspells to bringing in mass removal, Mardu Vehicles was the ultimate deck at adapting to a format
That is a no brainer