Yes, continuous effects can absolutely override or modify a card's printed creature type. Under CR 205.1b and the layer system (CR 613), type-changing effects apply in Layer 4, which directly alters what creature types a permanent has regardless of what is printed on the card. The printed text is just the starting point — in-game effects can change it.
These type-changing effects come from many sources: the permanent's own text, spells, activated abilities, triggered abilities, or static abilities from other permanents. For example, a card like Standardize or Arcane Adaptation can change a creature's type to any type you choose, completely replacing or supplementing the printed type.
When multiple effects change a creature's type, they interact according to the timestamp rule (CR 613.7): later-applied effects generally take precedence, unless one effect specifically says it sets the type 'in addition to' other types, in which case it adds without removing existing types.
Concrete example: You control a Grizzly Bears (a Bear creature). Your opponent activates an ability that makes all creatures become Saprolings until end of turn. Grizzly Bears is now a Saproling — not a Bear — for the rest of the turn, despite what is printed on the card. Any 'Bear matters' effects would no longer apply to it.
It's worth noting that some effects add types rather than replace them (e.g., 'becomes a Zombie in addition to its other types'), in which case the creature keeps its printed types and gains the new one. CR 205.1b and 613.1 govern how these layers stack and interact.
Unofficial fan resource — not affiliated with or endorsed by Wizards of the Coast. Answers are AI-generated estimates grounded in the Comprehensive Rules and are not a substitute for an official judge. Verify anything match-critical.