Fate Modifications

Cards
Along with the three or more usual Stunts, players get two extra special stunts representing their cards, which can be used only once per battle each . These stunts must help their partner in battle, rather than being something that they can do by themselves. These stunts can be freely switched at any time while in the HQ, and players can create a 'deck' as they make more of these. No more than 10 of these stunts can be in one player's deck.

Evolution Bonus
When a Digimon evolves, they will get a bonus while fighting with Digimon of a lesser evolutionary level. Consider humans as Rookie level Digimon when trying to fight one.

Rookie: No bonus.
Champion: +2 against Rookies.
Ultimate: +3 against Rookies, +2 against Champions.
Mega: +4 against Rookies, +3 against Champions, +2 against Ultimates.

Evolution
Every partner Digimon treats Rookie as its 'base' form, and will default to it while not in battle. At higher power levels, Champion can become the 'base' form.
At first, Champion is the only evolution a Digimon partner can take. As they defeat enemies and absorb data, however, they can eventually unlock their Ultimate form. Mega form will only be available as the plot progresses.

During a fight, an evolved Digimon can reset their stress counter by going back one evolutionary step.

Fate Modifications

Digimon: Argos Agency Rid